text:
Using Ocean bakes (from Ocean modifier) to Displace a Plane with Geometry Nodes - HOW?
I have created a near-perfect ocean for my scene using texture displacement.  Basically I just made two different ocean bakes and then used them blended together in the displacement channel of my plane.
However, I ran into an issue when I realized that I need Geometry Nodes for the spray effect.  My issue is that I can't figure out how to recreate my ocean with GN, so that I can then use the Ocean Spray bake to create points for the spray geometry.
PROJECT FILE
This what my material node looks like:

For this result:

How would I go about rebuild this node setup in Geometry Nodes?  Take note that I have two different bakes and they are scaled differently, then blended together.
I'm stumped on how to build a GN setup that would have an identical outcome, so that I can further amend the nodes to add Spray.

Not an answer, but perhaps a lead: I'm using the addon "Advanced Ocean Modifier", which uses GeoNodes to add spray. It's a paid addon, but sometimes it's cheaper to buy a setup than to figure it out by yourself :-)
This setup (including more complex material and no/less displacement I think) does render twice as slow as your cached solution over here. And your shader works in a circle, while the Ocean Modifier, basically a layer over the Blender Ocean deformer, uses rectangles. Circle seas give better horizons. But still, perhaps you can inspect their GeoNodes setup.

Hey man thanks for the tip.  Could you throw me a solid and post a pic of the GN setup that plugin uses for foam?

Alas: it's an experimental feature and I got a Python error trying to add it in a new document. Foam around objects works though: around floating ones and static objects (like the poles of a peer standing in the water)

All good man, thanks for trying.  Also, I apologize, I meant SPRAY... foam is pretty easy to manage with baking and material nodes.  I would kill to see the Geonode setup for spray though, if that's possible ;)

Yes do did I: SPRAY uses GN an throws an error, I just added that FOAM does work. Spray might work in an olde Blender, I’m on 3.3.1

it's crazy, I cannot find any information about how to create spray, and the documentation about that option is entirely vague in the Blender manual. It's driving me crazy.

I met the creator of Physical Sky And Starlight at Blender conference this year, he's working on an infinite ocean without tiles...


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World Environment HDRI vs. Sphere w/ HDRI texture over entire scene... is there a difference/advantage?
Is there an advantage, or a difference, between adding an environment texture to the World, vs. adding the same environment texture to a sphere and simply scaling it up to surround your scene?
The advantage of using a sphere is that you can easily rotate the HDRI without having to use Texture Mapping and Coordinates nodes.
I'm just curious if Blender processes the light information on the scene differently coming from a sphere vs. the World.

I may be wrong but I think it's the same, except your camera location and zoom won't be taken into account with an HDRI. Also, having to plug some nodes is not so tedious, you also need to do it for a sphere

The advantage is that you don't need to create a new geometry (the sphere) to add the HDRI, you basically created a Studio to light your object or scene

Thanks @moonboots and you're right it's not too tedious, but I do prefer to use a sphere.  I shoot scenes and HDRI's in the middle of those scenes, then I rebuild the scene in the viewport.  It is a lot easier for me to match up the background (HDRI) to the foreground plate by simply rotating a sphere until I get it exact.  I just wasn't sure what the implication would be in terms of how the scene is rendered using the sphere as a World environment.  Cheers.

source: Stack Exchange

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

sort: votes


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Why Won't My Gradient Volume Work?
I'm trying to make a fog that is so thick you can hardly see through it at the bottom, and becoming invisible up top.  I've made this setup but for some reason my volume seems to be ignoring my gradient texture, which you can see should be correct in the first image.
What am I missing here?
PROJECT FILE

Don't use the UV socket of the Texture Coordinate node, use either Generated or Object. The UV coordinates only hold surface information, so the inside value of the cube is some homogenous value overall.

I've done some changes from the pics you have applied, used a Separate XYZ node instead of gradient. Hope this will help.

The trick here is not only that you used a Separate XYZ node... but you are using the Generated output of the Texture Coordinate node. It would also work with the Object output and there would be no need for a Separate XYZ. The problem with the original setup is using the UV coordinates. I'm no expert, my guess is that the UV coordinates only map the texture onto the surface and don't take the 3D volume into account so that the inside of the cube doesn't get the gradient and is always homogenous, whereas the Generated and Object outputs have values throughout the mesh.

Yes, Sorry for that, I forgot to mention that part too, just realized it

It's okay, you mention you've done some changes. I just wanted to point that out because if someone thinks a Separate XYZ would be the solution - it's not. If you still use UV you will get a gradient on the surface as well, but still no gradient in the volume. As I said, the Separate XYZ isn't the key to the problem, the gradient works just as fine if you switch to Generated or Object. You only have to adjust the Mapping node and Color Ramp differently.

Thank you for taking the time to write an answer @Wiseman I really appreciate your solution

Ahh, I completely overlooked the UV input.  Total head slap moment!  Thank you for clearing that up @GordonBrinkmann, if you would like to post your comment as an answer I will mark it accordingly.

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


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Geometry Nodes: How to Iterate each Duplicate in an Array
I want to create an Array procedurally in a way that every iteration of the original geometry is calculated slightly differently.  Is it possible to do that?
In particular I want to make an object that is distorted along its normals (which I can do), and then I want to make an array of that object, where each iteration of the object is distorted more and more as I increase the number of objects in the array.
Can anyone outline how this might work?

You have no access to the (shared) geometry-data of instances created in GN.
You can give instances individual object-level transforms. (If you like, you can independently scale, translate, and rotate the vehicles carrying the instances, and the instances will follow, but you can't get at the cargo.)
In order  to manipulate the meshes of the instances individually, they must first be Realized. But that converts the instances into one big mesh.
So you must give the bits of that mesh a memory of which instances they were, by Capturing their instance-indices before conversion.
That means a tree something like this:

Hey Robin, thanks for weighing in here.  This is a really cool solution for applying global transforms.  But if I have my node tree set to displace all of the vertices randomly, how would I set it up so that each iteration gets a number added to an input (i.e. "seed" or "noise scale") for each duplicate?  I.e. Iteration 1 = X value, Iteration 2 = X value +1, Iteration 3 = X value +2, and so on.


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Driven Rotational Formula
I want to rotate a stack of planes using a control empty as the driver, but I want each plane to move a little bit more than the one below it.
What would the formula for this be in the driven properties?

why do you want a driver? you could simple use an array modifier...?

Rotate about which axis? You mean spin in their own plane?

@chris can't use an array because every object will be different

@RobinBetts Sorry, should have said: Z-axis, and yeah spin along their own origin

And is geometry nodes ok?

@Chris absolutely ;)

Remove any parent-child relationship, create an empty (control object), hover over its Z rot value and right click "Copy as new driver".
Hover over the Z rot value of the first plane and right click "Paste driver".
Hover over the Z rot value of the 2nd plane and right click "Paste driver", right click "Edit driver" switch from "Average value" to "Scripted expression" and set the expression "rotation_euler*2".
Copy this driver and paste on the third plane, edit the expression "rotation_euler*3".
Paste the driver on 4th plane and edit "rotation_euler*4".
And so on ...

Once again, thanks Josh!  Strangely, when I tried to do this per your last answer to my previous question, it didn't work with the rotation. I kept getting "python error."  No clue what I was doing wrong but it's working now so cheers.

Probably some little syntax mistakes, like capitals or spaces or dots.


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Help with Blender not "Honoring" Seams
I clearly have a seam marked but blender is not "honoring" the seam in the UV's. Is there a setting somewhere I could be missing? Here is some picks, any help would be appreciated!

You an see the selected face, I would have thought the UV's would be spilt along the edge I highlighted in orange. I was looking for a way to manually split them but couldn't find it.

I'm not sure from those cropped pictures how blender is not 'honouring' the seams. Can you be more exact in which seams you think are being ignored? You can use the [edit] link below your question to add more information to your question if you need to.

Have you tries selecting everything in edit mode and hitting "Remove Doubles"

Can you upload the .blend file using Blend Exchange so we can check it out?

Do you have duplicate verts around the loop that make another edge holding it together.

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


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Geneal Question About Creating an Add On
I am a .NET Engineer. I don't know Python though. I am trying to find out of this scenario is plausible. Could an add-on be created that could take an ID map that was created in Blender Render and multiple imported diffused textures (maybe as many as 20) and then could "bind" a color (from the ID map) to each one of the imported textures and create a single diffuse map from the 20 textures. I am wondering if the Blender API surface area exposes the functionality to handle these tasks. I understand that this maybe too vague, but if you have experience writing add-ons and you think it is possible I could write up the required stories with acceptance criteria for a more specific response, just let me know.
Here is and example of the ID Map using red as the color "bound" to a given diffuse Map.

I think you may be wanting to bake multiple materials onto one image.

Are you sure need it to be an addon?
Otherwise you can use Compositor Color key node to create mask from color, and then color mix node to mask out textures:

I want to be able to do like 20 at once. I don't want to do it manually. I could just manually do it in Photoshop.

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


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How to apply a force via python to a rigid body wheel
I have set up a simple car like model in blender 2.8

I have now set up a rigid body so I can simulate simple physics

Main Block - Active Rigid Body
Wheel - Active Rigid Body
Empty - Rigid Body Constrained

This exactly works as expected. When I set the constraint to Hinge, also the wheels are turning when the vehicle rolls down a test plane)
But I need to control the vehicle via a python script (Apply a rotation/force to the 4 wheels)
Therefore I've set up the following script
import bpy, time

# get the 4 wheels
wheels = [bpy.data.objects['WheelFrontLeft'],
    bpy.data.objects['WheelBackLeft'],
    bpy.data.objects['WheelBackRight'],
    bpy.data.objects['WheelFrontRight']]

for wheel in wheels:
    wheel.animation_data_clear() # clear keyframes
    wheel.rotation_euler[1] = 0 # reset rotation

for i in range(1,50): # step through 50 frames
    bpy.context.scene.frame_set(i)
    for wheel in wheels: # iterate wheels
        wheel.rotation_euler[1] += 15 # rotate +15
        wheel.keyframe_insert(data_path="rotation_euler", frame=i) # insert keyframe

Unfortunately this does not change anything...
After running the script I got a totally messed up scene (everything is wrong positioned/rotated) and if I restart the animation, the vehicle just keeps falling (Only the Rigid body simulation applies without the rotation)
So I don't see any rotation at all. Only when I'm checking the animation checkbox (for the active rigid body wheels), the wheels are moving. In that case the car is not falling anymore (physics won't be applied).
Obviously that is an either or switch for physics/animation
I also tried setting the empty constraint type to Motor instead of Fixed but then it just falls apart....
Also rotating the constraints does not help at all....
What am I doing wrong? How can I fix this?

Rotation in blender uses radians.  Adding 15 to euler rotation y is actually adding degrees(15) or ~860 degrees to your rotation. . Consider adding rigid body "animated" property keyframes of wheels as True at say frames 1 and 49, then off at 50. as in  https://blender.stackexchange.com/questions/5100/how-can-i-add-motion-to-a-rigid-body

No i dont want to animate all... I just want to control the velocity of the wheels via python - the rest should be done by the physics system

I just got it working myself.

The solution is the motor constraint. Using the motor constraint alone, the vehicle will fall apart. Thus you have to add another constraint between each vehicle and the body - a hinge constraint to only allow rotation.
Thus the complete setup looks like this

Create the vehicle (body and 4 wheels as seperate objects)
Create a Hinge Constraint between each wheel and the body (I used an empty for it - take care of the right rotation)
Create a Motor Constraint between each wheel and the body (Angular movement - I used an empty for it - take care of the right rotation))

Now you can check out the context menu of the angular velocity. There you can find the option "Copy Data Path". This will copy the relative property path of the object to use it withing your scripts

Then you can use it for example like this
constraints = [bpy.data.objects['fl'], bpy.data.objects['bl'],
    bpy.data.objects['br'], bpy.data.objects['fr']]

for c in constraints:
    c.rigid_body_constraint.motor_ang_target_velocity=5
    c.rigid_body_constraint.motor_ang_max_impulse=100


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Precise Box creation (migrating from 3d MAX)
I'm migrating my primary 3D tool from 3D Max to Blender.
I Just missing to create a precise form. for instance: create a 10x14x12 Box. The For now I'm only able to create an 1x1x1 cube, and them inaccurately move its vertices to a proper position.
Is possible to create a predefined size basic form like this?
Thanks

Look at some ways here - http://blender.stackexchange.com/questions/274/how-to-model-effectively-using-exact-measurements

Possible duplicate of Set dimensions of a mesh

Sorry, it was not i was looking for. I want to create a mesh based on parameters.

If you have a particular kind of workflow in mind, try to describe it in the question section, so we can try find something close.

Migrating from 3DS Max myself, I understand your concerns, yet Moving, Rotating and Scaling in Blender are very precise tools, unless you mean to achieve them in an approximate way, I believe Cegaton already answered your direct question in the best way possible, so I'll include some additional methods in my Answer concerning moving precisely that you mentioned on the side in your question.
In Edit mode, which you access using Tab, you can select the face you need to move, press G "shortcut for move" then the letter associated with the axis you need to move on, for instance Z to move on the Z axis, then enter the value, keeping in mind the units you are using, so if you are using Metrics, and you want to move the Face / Edge / Vertex 10 cm, enter the value 0.1 followed by Enter, this will move the selected sub-object on Z axis 10 cm in the positive direction, in case you need to move it in negative direction, use the - before the value, pretty straight forward, the same method works for other Transform tools, for Rotation (in degrees) and scale (in percentage), if you do the Scale in Edit mode, you don't need to apply the scale using Ctrl+A, the same method apply in Object mode for Moving / Rotating / Scaling objects, but you need to remember to apply scale, this will become a second nature very soon.
In Edit Mode, if you need to transform a sub-object using it's normal, you can achieve that by selecting it,  G  for moving,  R  for rotating,  S  for Scale, then  Z  twice to translate it on normal Z axis, same applies for X and Y axes. Same thing applies in Object Mode if you need to transform the object using it's Local Space.
Keep in mind that Blender automatically assigns the shortcut of pressing axis letter twice Z Z, XX or YY to Normal if you didn't change the transformation orientation, which is set to Global by default, if you use View for instance, then got back to Global, pressing the axis shortcut twice will assign the View axis, not the Normal axis.

Another tool concerning precision, and in my opinion, worth alone migrating to Blender, is the measurement options, you can enable few check boxes, to get accurate dimensions of selected faces or edges, angles and even areas

Notice in the image above, in the menu, under Mesh Display, I enabled Length for Edge info and Area for Face info, in the 3D View "Viewport" you can see the related info, you don't need to use the tape to measure any more, of course blender has also a Ruler tool in case you need to take dimensions not related to edges or faces.
Another useful tip, at least I find it useful, is to enable the Enter Edit Mode in the User Preferences Menu under Editing Tab > New Objects

This option will save you a step, in case you edit immediately most of the objects that you create, hence it will automatically enter Edit Mode once the object is created.
Another option you might find useful coming from 3DS Max, is Enabling Auto Perspective option in the User Preferences Menu, under Interface Tab.

This option will convert the view automatically to Orthographic view when you change your view to Front, Side, Top...etc. And it will automatically revert to Perspective mode when you Orbit the view.
Keep in mind to save user settings when you change them if you want to keep the changes whenever you start Blender, also you will need to save Start Up File in File menu, be careful though, this will keep everything you have in the scene saved as start up file, so make sure to do these steps when you have Blender exactly as you want it to start a new document, for instance, if you are working on a project, and you save start up file, then whenever you start a new file, you will have the project there, with all the objects, cameras, lights...etc.
Happy Blending :)


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Gummy Bear and Gummy Worm materials
i tried to make realistic material of gummy (jelly ?) but somehow it doesn't look real as i want, I research all over forums and google, like material of Doki on the forums (https://blenderartists.org/forum/showthread.php?350580-Gummy-Worms-and-Gumdrop).
Here is what i got:

What I want to make:

Here is my blend file: https://drive.google.com/open?id=0BzM1zdTMJ5omZVM4alpDLVJRdWs

Related

@batFINGER on my file is actually the node of Doki on the forums. I'll edit in the post

Here is something that looks close.
Please excuse my gummy model, The first picture uses the new Principled shader and the second image uses just a glass shader. If you use the glass shader make sure you use a Fresnel and glossy node mixed in.

Use the Principled shader with transmission to 1 for glass.

In the base color slot connect a color ramp with "constant" selected and choose any colors you would like (this is optional). Also You will need to change from the Constant to something else for the Gummy Worm, so it has a nice fall off.

3.Add the Object Info node so the computer randomly picks a color.
4.Pick any rough looking texture and plug in into a Color Ramp node (so you can control how much you want by sliding the flags). Make sure on the texture image you set it to Non Color Data and either unwrap your model or connect the other two mapping nodes so Blender knows where to put the grunge texture.
Just use a texture to have clear and "foggy" sections of the model, and plug it into the roughness socket.
I didn't do it here, but you can grab another texture with divits in it and plug that into the normal socket to add more realism.

This is the grunge texture I used.

You should probably add something in your answer stating not to download the latest 2.8 build if you are using the model in production or saving important files with it (https://builder.blender.org/download/)

Thanks you. your node look awesome, btw what kind of textures you using ? i'm change some textures image but if i use some black and white dirt map, it's doesn't effect the model much, if i use some concrete texture that will make the bear too thick.

ohhh I got it, if my textures too thick or too thin, i can use the the blacknwhith color ramp to get how much dirt i want on the model.

@cegaton Done,  I added the texture. If this node set up worked for you please mark the answer as accepted, to better help others in the future, and help me get as many points as cegaton. lol

@icYou520 thanks you for the detail. Help me much in understand how this node working. Love you :D.

@Squirrel where does he mention 2.8?

@Neil The "Principled BDSF" Shader will be available in 2.8, however, you can get a test build of 2.79 that also includes it. Same rules apply though.


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How to generate a metal mesh?
How can I model a metal mesh in Blender? I have tried to create a texture with opacity, but I cannot seem to get that to work. Is there another way to create this?
I am using cycles.
Thanks!

EDIT: Hey thanks everyone for the great advice! Before this I was not sure where to start, but now I have plenty of ideas about how to tackle this!

Did you try wireframe or skin modifiers on subdivided plane?

¿¡ How can everyone ask a question like yours and get 400 views !?  ¡ I wish I knew your secret !

@Denis This was the info I was looking for! I really had no idea where to start.

Create a plane and subdivide it few times.
Select the plane and poke the faces using Alt+P shortcut.

Select all the horizontal and vertical edges and dissolve X > Dissolve Edges

Add a Wireframe or Skin Modifier

"Select all the horizontal and vertical edges": It will be helpful if you describe how to do it other than selecting hundreds of edges manually (I have subdivided it by 100 times).

If polygon counts are nor an issue and you wish to keep your workflow as modular and non destructive as possible (which I always strive to accomplish) you could achieve this easily with only a bunch of modifiers on a simple plane, no modeling or texturing required.
It should also keep it relatively simple if you later need to make more complex shapes or bend your mesh in more ways.

Add a simple plane
Add a Subdivision Surface modifier
Set it's subdivision type to Simple
Set the number of both render and view subdivisions to a number that suits your mesh size.
Add a Decimate modifier
Se it's type to Un-Subdivide
Add a Wireframe modifier to build the actual mesh
Optionally scale it horizontally to make the mesh with the correct proportions.


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Blank Texture on Cycles GPU Baking (AMD)
I'm having problems for baking texture through GPU in Cycles.

Baking through CPU is working. (Very Slow...)
Render preview on 3D View through GPU is working.
Render through GPU is working.

Although I'm using Bake Type Combined, I'd also tried Diffuse and, unfortunately, got the same result.
My GPU is an AMD R9 390 (8Gb) with the last driver version (17.5.2) and I'm running Blender 2.78c on Windows 10.
Really appreciate some help.
My baking options:

My render options:

My User Preferences:

Does CPU baking work as expected? AMD GPU computing is not as well supported or on par with NVidia feature set for the 2.78 series. Either use CPU or try a newer 2.79 testing builds at your own risk, OpenCL support as been thoroughly improved and is roughly on par with CUDA

The CPU baking is really fine, but slowly as expected. I'll give a try to 2.79 then, but I never tried testing builds... Could you please give me the download link !?

Check the "Bleeding Edge" link in red at the bottom of https://www.blender.org/download have in mind that these are unreleased testing versions, bugs and kinks are expected. Save your work often, make safe copies if necessary. And please, for the love of God, stay away from the 2.8 builds for the time being, they are not ready for end users yet, so do don't go complaining about errors and missing features.

The Blender-2.78-94a3bc6-win64 give me exactly the same results as the 2.78c. But Blender-2.78-58a434b-win64-vc14 works like a charm and it's noticeably way faster. Finally I got GPU baking on my Radeon !! Do you mind to post an answer, so I can mark as answered and solved !?

Posted below, you can thank AMD for their great support and dedication sponsoring development for improved Cycles OpenCL support.

AMD GPU computing is not as well supported as NVidia's solution, and definitely or on par in terms of feature set as of the Blender 2.78# series.
Either use CPU baking or try a newer 2.79 testing builds at your own risk. Cycles OpenCL support will be thoroughly improved and will roughly be on par with CUDA in terms of features and support as of Blender 2.79#.
At the date of writing Blender 2.79 is not released officiall yet so if you want to try it you must use development testing builds.
To do so head over to https://blender.org/download , and check the "Bleeding Edge" link in red at the bottom.
Have in mind that these are unreleased development versions, meant for testing purposes and not recommended for production; bugs and kinks are expected.
Save your work often, make backup copies of your files if necessary.
And please, for the love of God, stay away from the 2.8 builds for the time being, they are not ready for end users yet, not even for testing purposes, so do not ask about or report any errors or missing features you my find.


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Texture not visible in material preview
I've assigned material with textures and it displays properly in viewport, however, material preview still doesn't show my texture:

Same thing in Material tab, the texture doesn't show, it's only a white sphere. Am i missing something?
BTW. Why to assign material, we must enter the Edit mode? It's problematic when assigning material to many different objects. Or maybe again i'm missing something here? :)
Blender file:

Could you post a .blend file, using a service like Blend-Exchange, or add more screen shot of all your material and texture settings/nodes? There are many things that could be causing this and more details would be very helpful

I've posted my .blend file (updated the question). I'm just trying to do basic material things, like assign textures with normal maps, specular maps, etc. I'm new to this, so maybe there is a little checkbox that i need to enable, or something like that...

BTW, you should have packed the texture in with the .blend file...

Strange, when i open this blend file the texture is already there and displays on the mesh... | Edit: OK, i've downloaded it and this file doesn't have texture, which is strange, because the exact copy of it (in my folder) has textures in its file. I don't know what's going on here, i'll try fix it asap

OK, i've selected checkbox "pack the image" next to the texture, now it should be inside the file. I've updated my question with new blend file.

Should I delete the old one?

Yes please, i don't need it.

The texture is showing up as completely black, it is the Specular that adds the white. Very unusual.

Make sure you select the desired UV Map you want to use (Uvset1) under  Mapping. It is working perfectly for me

Yes, it's set to 'uvset1' but nothing changed. But as you can see, on the mesh itself, the texture is displaying properly. Only material preview window can't render it.

Tab into edit view and select all in the UV Image Editor

I did that, and nothing changed, material preview sphere is still white/black. What's this for? - Maybe it's something with my graphical settings in Blender? If i understood correctly, in your case the material preview is working and displays the texture on it?

The texture is setup correctly, but you have mirror enabled with reflectivity set to 1. This means that the material is entirely reflecting the environment around it, but as the mirror color is black, no light is actually reflected.
If you disable mirror, the texture is visible:

Note that I also set the specular intensity to 0, otherwise the texture is a little difficult to see (but visible).


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Bone unwanted rotation when moving IK
I'm making a rig from this tutorial: http://vimeo.com/30078317
And i have problem like this:

As the title says and GIF shows it is probably a problem with IK, but i don't know how to fix it.

Move your pole-target bone in front of the knee, when you've done the setup as in the tutorial at 19:30 this should work. The IK solver tries to maintain the orientation of the knee to the pole target. That is the reason why the leg is winding .


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Fluid render has horizontal lines in Blender Eevee
I am trying to render a fluid simulation in blender eevee but horizontal lines appear in every frame. Can someone help me out?

It's been a while, did you figure out what was the problem?

I was testing fluid simulation here and had the same issue. The solution was to turn off "Show Backface" in the Material settings tab, under "Settings" like in the screenshot below. Then the lines don't show up anymore.


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Removing all meshes from a collection with Python
I have 2 collections in a scene (collection, items) both with objects (meshes, camera, lights). How can I select all objecst of type mesh from items and delete them?
bpy.ops.object.select_all(action='SELECT')
bpy.ops.object.delete(use_global=False)

With that I can delete all from the scene but I want to limit it to delete all meshes from items. Probably I can if the collection name and type mesh but maybe there is a simpler way?

@Ray Mairlot, i'm actually  trying to convert your Slider Puzzle script from 2014 to blender 2.8

Don't think there is a simpler way (as you mentioned in the question).
Globally:

Get the collection
Iterate over mesh objects in the collection
Keep its inner mesh data
Remove the object

Then (optional):

Iterate over the collected meshes
Look if it has became orphean (no user)
If yes, delete it

Commented code:
import bpy

collection_name = "items"

# Get the collection from its name
collection = bpy.data.collections[collection_name]

# Will collect meshes from delete objects
meshes = set()

# Get objects in the collection if they are meshes
for obj in [o for o in collection.objects if o.type == 'MESH']:
    # Store the internal mesh
    meshes.add( obj.data )
    # Delete the object
    bpy.data.objects.remove( obj )

# Look at meshes that are orphean after objects removal
for mesh in [m for m in meshes if m.users == 0]:
    # Delete the meshes
    bpy.data.meshes.remove( mesh )

thanks a lot, that work great for me

Works great :) thank you


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Trouble making UV for plane shape
I'm trying to import a shape into Unreal Engine 4, but it's giving me a lot of problems after trying to build the lighting. I think it's because my UVs are jacked up and not proper.
Thing is in blender, I can't get my shape to properly unwrap.

https://i.sstatic.net/vhdcp.jpg
The UV isn't appearing for both sides of the plane.

https://i.sstatic.net/JQkQ3.jpg
I'm wondering if that's one of the issues. Also, I don't seem to have any faces in my shape. I tried Ctrl+R, but no lines will appear for me to make. Also I've solidified the shape, so both front and back of the plane should be working.
Pretty lost. Any thoughts? (I'm very new to 3D modeling)

Hi. Please add images directly into the question body. See: https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post

Be in Front Ortho (Press Numpad 5 and Numpad 1)
Go to Edit Mode
Extrude all the faces. Select the top and bottom faces
Press U -> select -> Project from view (Bounds)

Now jump to UV Editor and hope you get a good UV.

Thank you very much for your input. This still only gives me one side of the shape in the UV editor though. I was thinking I should be having two sides represented in the UV editor, the front and the back.

You need some thickness to have both side image. Check the above answer edited


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Why are all right bones not connected with the mesh?
I'm new to blender and I recently made a model by my self and today I‘m finally going to connect it with bones! It looks all right:

But look what happens to the arms and legs:

Why are all right bones not connected with the mesh?

perhaps share your file: https://blend-exchange.giantcowfilms.com/

Perhaps select your object and in the Properties panel > Data > Vertex Groups, on the menu on the right of the list, there is a drowdown menu, click on Delete All Groups, then reparent With Automatic Weight? Not sure though...

Hi and welcome to Blender Stackexchange! To get helpful answers quickly please consider adding a blend file if possible. Also describe how you reached the current result and what steps you have tried to solve it so far. You can edit your question to add additional information. Have a great time on Blender Stackexchange and happy blending!

Thanks guys,i found out that i DIDN'T apply the mirror modifier!stupid me,now it works perfectly!


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Axis flip when converting matrix4 to quaternions
i have a hard time figuring out why i get an axis flip when i try to convert the second matrix to quaternion. First matrix (f1) gives me positive quaternion values while the second matrix (f2) gives me negative values in x, y, and z. If i convert to euler instead, the values are stable ...
Am i doing something wrong?
Thanks alot for your help!
from mathutils import Matrix

print("\n")

f1 = ((-0.8030, 0.2867, 0.5255, 1),
      ( 0.2980,-0.5660, 0.7686, 1),
      ( 0.5161, 0.7729, 0.3691, 1),
      ( 0.0000, 0.0000, 0.0000, 1))

f2 = ((-0.8153, 0.3279, 0.4773, 1),
      ( 0.2633,-0.5243, 0.8098, 1),
      ( 0.5158, 0.7859, 0.3412, 1),
      ( 0.0000, 0.0000, 0.0000, 1))

matrix_f1 = Matrix(f1)
matrix_f2 = Matrix(f2)

quat_f1 = matrix_f1.to_quaternion()
quat_f2 = matrix_f2.to_quaternion()
euler_f1 = matrix_f1.to_euler()
euler_f2 = matrix_f2.to_euler()

print(quat_f1)
print(quat_f2)
print(euler_f1)
print(euler_f2)

No, you are not doing anything wrong. It is rotation expressed as a normalized 4-dimensional vector. Do not worry about the values there, if they need to be negative that is fine - it is still a representation of the same rotation, it is only expressed in a way that makes some math easier. It is really hard to make sense of quaternion values just by looking at them.
You can make a plane and test the rotations on it. You need to set the rotation mode to quaternion in the n panel to be able to change bpy.context.object.rotation_quaternion and see it on the object.
If you create another plane and run the script again changing the rotation in euler mode for bpy.context.object.rotation_euler instead, you will see the rotations match despite the negative values that happen to exist in a normalized 4-dimentional vector notation of the rotation. You can add this to the end of your code to see this. You will need a new object created and selected as the active object:
import bpy
#bpy.context.object.rotation_quaternion = quat_f2
bpy.context.object.rotation_euler = euler_f2

You will be able to observe floating point/binary conversion precision errors if you decide to compare the results of quaternion to euler conversions by the numerical values doing something like this:
print( quat_f2.to_euler() )
print( euler_f2 )

The rotations are the same. Numbers differ because of the precision errors during the calculations. That is normal.
If you need to interpolate between the quaternions you face a problem that the same rotaion can be expresed with a negative and a positive quaternion and it is possible to rotate the long way or the short way around to the same rotation. If I am reading this correctly, the short path would be between two quaternions the dot product of which would be positive, so you can check if your current rotation from the previous is the short one evaluating if the dot product of the quaternions is negative or positive and then negate your current quaternion if needed:
if quat_f1.dot(quat_f2) < 0:
    quat_f2.negate()

Thank you very much for your answer Martin, i really appreciate it!
I should have been more clear though, i am writing an importer for a custom camera file format. The file contains a 4x4 matrix per frame. I set the .matrix_world of the new camera accordingly and set the keyframe in quaternion rotation mode. Position and orientation are working as expected. The problem is that if the quaternions switch to negative from one frame to another the camera rotates around all axis and the motion blur is going crazy. Euler works but fails on other frames.
Any ideas?

I think the edited answer should help.

This worked out perfectly! Thank you very much for your help Martin!

@ManuelGrad If this answer solved your problem, please mark it as accepted by clicking the checkmark on the top left of the answer.


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How can I test the Blender 2.8 game engine on Linux?
I know that I'm not allowed to ask questions about unofficial releases of Blender but this is a more simple one: where can I get the game engine for Blender 2.8? I am interested in porting my latest game to it since it's finally somewhat stable. I have seen numerous videos of people using UPBGE with 2.8 like here but none of them provide a link to download the engine. I installed the Git version on my Ubuntu 17.10 install but it ended up just being BGE 2.79. Does anyone know where to get the 2.8 Blender Game Engine that has EEVEE for the game engine? UPBGE 2.8?
(Also, in case anyone is wondering, NO! The official test builds don't have a working game engine. When you press P everything disappears and turns gray.)

Like you mentioned the 2.8 builds do not yet have anything for the game engine. As of now you will want to use a ported version of the BGE, such as UPBGE.

After you clone blenders git repo, checkout branch blender2.8 and then build it to get the current work on blender 2.80

I also thought that it was worth mentioning that in the UPBGE 2.8 that I'm using it is amazing how superior the collections system is compared to the current layer system! I am porting some of my games to it and I can tell you firsthand that I never want to use the layers system again! If only EEVEE supported modifiers!

As far as I know, there is no work being done on 2.8's game engine at the moment (Feb 2018). Eevee is a viewport rendering engine and has not made its way to the BGE yet.
As for UPBGE, it seems there is some work being done on getting Eevee shaders to work there back in last year, but stopped.

There is no "official" Blender game engine with EEVEE yet and the official Blender 2.8 from Blender doesn't have a working game engine at all. There are still third parties, however, that do use EEVEE in the Blender game engine. Thank you for responding though! ;)


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Advice on how to remove these weird black shadow things?
I am not sure what to do with these vertices to fix this weird pinch I have. It creates weird shadows and looks bad. Here are some images.

I could probably just delete a big chunk and try again but maybe this will be a good learning experience for the future to learn other ways to fix this. Thanks a lot for the advice!

The pinch looks like what Josip  said, but the shading looks more like flipped normals. Select all vertices in edit mode and hit Ctrl-N to recalculate the normals.

It looks like there is a Face/Polygon inside the handle, deleting that face will fix the shading problem.


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Hiding and unhiding a Collection in the Viewport
This may have been asked before, but I cannot make sense of it. I need a script which simply toggles the eye of my collection named "Animation".
I have enabled my viewport by using bpy.data.collections["Animation"].hide_viewport = False
The eye however is closed and I need to open it with a script. Any help is appreciated.

Have you tried accessing collection from view layer?
bpy.context.view_layer.layer_collection.children["Collection Name"].hide_viewport = False


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Moving and rotating using CSV
I have used the script to move an object using CSV. Can it be modified to include rotation as well? Can this be done using one imported file, or is it best with two imported files. One for Location the other for Rotation.
The object needs to move and rotate using all csv coordinates.
import bpy
import csv

f = start_frame = 1
frames_per_row = 10
csv_path = "C:/Book3.csv"

ob = bpy.context.object

with open(csv_path) as file:
    csv = csv.reader(file, delimiter=",")

    for row in csv:
        ob.location = [float(v) for v in row[:3]]
        ob.keyframe_insert("location", frame=f)
        f += frames_per_row

This is a somewhat trivial task given the code is basically already there
Data contained in the same csv with columns like:
loc_x,loc_y,loc_z,rot_x,rot_y,rot_z
import bpy
import csv

f = start_frame = 1
frames_per_row = 10
csv_path = "C:/Book3.csv"

ob = bpy.context.object

with open(csv_path) as file:
    csv = csv.reader(file, delimiter=",")

    for row in csv:
        ob.location = [float(v) for v in row[:3]]
        ob.rotation_euler = [float(v) for v in row[3:6]]
        ob.keyframe_insert("location", frame=f)
        ob.keyframe_insert("rotation_euler", frame=f)
        f += frames_per_row

If two files need to be used you can either zip them beforehand or keep track using the keyframe. It is also possible to use quaternion rotation.

The script I used in my post works perfectly with either the location or the rotation. Once I  use both together (as in the answer) they do not seem to work. All my locations are in columns 1 to 3 and my radians are in 4 to 6.

I think this one is the culprit as it works with a 3 column CSV file but not a 6 column CSV "file ob.location = [float(v) for v in row[:3]]"  From what I see the columns can be set, so [3:6] means that it starts reading at column 3 and stops at 5.


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Exporting mesh as CSV file
I have been using this script to export my mesh to a CSV file. The problem is that every time I select a new object, the file is overwritten, so ideally when selecting a new object I need it to write a new CSV file, perhaps like this.  "mesh_001.csv", "mesh_002.csv" etc. Please could someone assist.
import bpy

outputFile = 'C:/My_Objects/mesh.csv'

verts = [ bpy.context.object.matrix_world @ v.co for v in bpy.context.object.data.vertices ]

csvLines = [ ";".join([ str(v) for v in co ]) + "\n" for co in verts ]

f = open( outputFile, 'w' )
f.writelines( csvLines )
f.close()

Use the name of the object as the file name
import bpy
import os

name = bpy.context.object.name
outputFile  = bpy.path.abspath("//csv_export\\" + name + ".csv")

print(outputFile)

If I save my file in D:\ and my object is named Cube, the outputFile will be D:\csv_export\Cube.csv.
Increase a suffix number for each export
import bpy
import os

index = 0
while True:
    path = "//csv_export\\mesh" + str(index).zfill(4) + ".csv"
    outputFile = bpy.path.abspath(path)
    if not os.path.exists(outputFile):
        break
    index += 1

print(outputFile)

In this script, we initially construct a path to a file with the suffix 0 => mesh0000.csv. While a file already exists at that location, we increase the counter.

It doesn't seem to create the new directory D:/csv_export and if I create it myself nothing is written into it when I run the script.  My .blend file is saved in the same D:/ directory. Maybe I'm doing something wrong?

What code did you run? Was is this?

Using the name of the object as file name.

Do you comprehend the script you posted?

I am not an expert at python, sorry. I sort of understand a few things. I am learning as I go.

The code snippets of my answer simply set the ouputFile variable. You still have to use the code in your Q which saves the file. I have combined them in the link given in my first comment.

In the example above, is it possible to create the directory folder D:/csv_export/ first,  before the csv file is written into it?

https://thispointer.com/how-to-create-a-directory-in-python/


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How Do I Fill This Bowl With Balls?
I have a rigid body setup but I can't figure out why my particle objects won't fill the bowl.
I have rigid body set for the both the ball object (active) and the bowl (passive), scales are applied, but the particles just keep dropping without interacting with the bowl.
What am I doing wrong?
Project File

you cannot. Particles do not collide with themselves. So you should use rigid bodies.

Ah, gotcha, I should have known that. Thanks for chiming in.

yes, unfortunately, there is no particle collision. But you can fake it.  https://i.sstatic.net/SvcVX.gif Turning the bowl over so that everything falls out might be a bit tricky.


text:
Using Geometry Nodes, how would I build a procedural surface texture?
I want to wrap a base shape with a pattern of smaller objects, which will either extrude from or bool (difference) the surface. Below are some real world examples of the kind of objects I want to create.
I would love to know some methods for how to achieve this.  I know there are many ways to skin a cat, so I'm very keen to learn some different approaches.

Take a look at Tissue addon which comes by default with blender

Thanks for the suggestion @retr0, seems great for organic textures but I'm looking for more geometric/procedural. Cheers.


text:
Quick Select Parent and Child Objects in Outliner?
Is there a simple method for click-selecting an Object in the Outliner and also selecting its child Objects, in one go?  (Like holding Shift and clicking, for instance, though I know that one doesn't work.)
Eg:
I have a bunch of objects with child objects in them.  I want to drag them into a new Collection.  If I drag just the parent and move it then all of the child objects stay in the original collection.  (I find this to be an infuriating flaw in Blender's UI, but I digress.)
I know I can select the parent and then hold shift and click the last child object to select the hierarchy.  I also know that I can right-click and choose "Select Hierarchy."  Both options become tedious when you do them enough.
If there is a better way I would love to hear it!

In the 3D viewport, this is easy.  It's shift ], shift [.  Unless it depends on initial startup interface choices, which isn't easy to check.  It's "select hierarchy" operation, with "child" and "parent" respectively, on extend.  (Shift on a selection is usually extend.)
That's not outliner, and there are outside cases where that won't work for you (parents or children in hidden collections), but it should be good enough most of the time.  Selections are echoed between outliner and 3D viewport, so selecting in 3D viewport will also select in the outliner, ready to be dragged to some hostile new collection.  (Poor objects.)
If you don't want to move your mouse off the outliner to call from a 3D viewport, you can still invoke a "select hierarchy" operation from a search there, but you'll have to adjust the operator settings manually, and it still won't select objects in hidden collections.

Thanks for your input Nathan. I'm aware of all of these functions, sadly none of which are the simple solution I'm after. Cheers.


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Why is my Shadow Catcher not transparent?
I'm doing everything I know how to do, but I must be missing something because my shadow catcher isn't working.  It receives a shadow, but instead of becoming transparent, it just gets dark.  (Using Cycles, and I do have Transparent enabled in the Render settings.)
This is my setup:

Enable "Shadow Catcher" in the Object Properties
Enable "Transparent" in the Render > Film settings
Background image > Emission Shader
Foreground Object over Shadow Catcher Object
HDRI to light the scene

This is what happens:

Why doesn't the rest of the Shadow Catcher (marked in yellow) become transparent?
I know there is a way to do this in the Compositor, but I would assume it is also possible to set up the scene without having to do that, no?
PROJECT FILE

Is there any reason to have "transparent" turned On eve if you are going to render with a background?

Hey @Emir, on hindsight, you're right there is no point. I watched a tutorial where someone used the Shadow Catcher (but in a different context) and said 'make sure you have transparent turned on in the Film settings' so I just did this without thinking it through ;)

If you check it closer, you can see checker pattern in black - it means it is transparent ... but shadow catcher does it transparent through entire scene :)
Using shadow catcher feature expects you want to do composition ... so you should mix fg with bg in Compositor.

In some scenarios you can try ...
Cycles
Disable Shadow Catcher and change material of your plane. Here the material is used for back plate and floor plate. The trick here is to use Window Texture Coordinates for texture mapping.

Based on your comment ... I don't think there is a native way to do it in Cycles ... try this Eevee setup.
Eevee
In Eevee you can trick it by using Shader to RGB node ... plus under Material Properties > Settings >

Blende mode set Alpha Blend
Shadow Mode set None.

Just trying to follow your answer: 1) You're saying that you have to do this with compositing.  2) You're saying that I could simply add the background texture to the ground plane object and let the shadow fall onto it.  This would be fine, except that I am building a scene with a background that is set to shadeless (i.e. an emission shader that won't take shadows), and I want to add a shadow onto it with a Shadow Catcher, but without having to use the Compositor.

Sorry I don't have a solution for you, just another workaround with Eevee (I know you asked for Cycles, but I don't know any other then Compositor). Maybe someone with programming skills to write an OSL shader ...


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How do I get the 'Fracture' panel to appear in the Toolshelf?
What must I do to get the "fracture" panel to appear in the 3D View Toolshelf? I have download the "Blender fracture; version --> 2.79a".
I have made a picture of a Youtube video where I can see that they have the "fracture" panel (I have made a orange circle around the 'Fracture' panel):

No, this addon is bundled with the Fracture Modifier Build, it should be inside the "fracture_extra" folder within the zip file which contains the build. ("fracture_helper.py") Alternatively you can separately download it here:
http://blenderphysics.com/fracturemodifier/
(Helper Addon)
The addon might also be updated separately from the build from time to time.

This is an addon which one should install separately.
Download it here:
https://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Object/Fracture

Please answer in English and edit your answer to explain how this link helps.


text:
The armature stays in the air instead of falling
If I click on Alt+A the armature (rigged) doesn't fall, it just stays in the air. I tried to add a "rigid body" but this doesn't help.
(sorry about my english-speaking)

afaik, you can't enable an "armature" (as blender object) as a rigid body... you can just use rigid body constraints on it...  see this maybe related  answer https://blender.stackexchange.com/questions/41235/rig-that-reacts-to-gravity


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How are the floats (0.0 to 1.0) mapped to ints (0 to 255) for pixel colors?
I'm fighting somewhat with Blenders image creation module. I struggle to map my calculated colors to the required range from 0.0 to 1.0. I need it to be very precise.
For example: I have a value 0.5 that will result in a value of 128 in the related color channel of the image. Then I have a value of 0.50390625 that I expected to result in 129, but becomes a 128 as well. Is there a formula or a list somewhere that shows exactly what ranges of floats are mapped to what integers? Or maybe someone can point me to the source-files, then I'd try to figure it out by myself. (I tried to locate the source file for this module but couldnt find it.)

Hi. How are you setting the colours? With code (if so, then please show the code) or via the UI?

Hello Ray, I'm tryin to export simple 3d-models into a texture. The xyz coords of the vertices will become the rbg values of the textures (this format is used in some virtual worlds). For example a value for a color channel is calulated like this: tmpx = (vert.co.x + (boundingBoxSize/2) - xrange) / boundingBoxSizeX

If that code is relevant to your question I suggesting adding that in.

its not relevant, since I would like to know how the Blenders image module turns floats into integers :)


text:
correct cycles node arrangement
Good Afternoon! anyone have any suggestions on the correct node arrangement here? I've tried a couple but nothing is working. Thank you in advance for your help!
Here is how it is supposed to look. this pic is from Noesis, a program used for viewing and exporting game .DATs
here is the unrendered view in blender

here is the rendered view, and wherein the problem lies. I appreciate the help my friends!

EDIT: here is the .blend and textures
https://mega.nz/#F!zaxGCaCa!d09bEVsqxvSnL9_AoRMZSw

It looks like you may be missing a texture in your material. Is is possible there is more than one image that should be used here? The black and white wall material looks like the kind of image that would be used to control the transition between to materials.

perhaps. now that you mention it i looked through my textures and couldn't even find the one with bricks on it. How can that be though if the bricks show up in the unrendered view?

When you focus on the transition from the brick wall to the white wall you will notice, that in the original game engine, there is specks of white paint over the brick wall, in the blender engine there is only brick and only white, and in the cycles render there is only the white specks visible. I strongly suspect, that your texture image has a lot more channels than you expect it to have. If you could share the texture file it would probably be possible to devise a node setup that extracts all channels properly and let's you render the scene correctly

appreciate the help, i admit nodes are challenging to me. files are up

The exporter you are using, seems to have some problems:
First the alpha-channel for the texture with the bricks is wrong. The alpha channel with the bricks is set to transparent whereas it should be opaque.

While this could be controlled with a node setup, the bigger flaw is that the wall consist of two meshes, each with a plane occupying the same space which leads to z-fighting -

leading to artefacts in the final render.

To get to the final render I set up the nodes for alpha channel in cycles like explained in "How to apply textures with alpha channel?"
The problem with z-fighting is described here.
If you need to get this to work, I suggest, you clean up the geometry of the wall (remove the overlapping part, probably needs a fix for the UV-mapping as well) and set up the nodes with transparency to account for the alpha-channel, while excluding the brick texture.


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How do I make 'Selection only' off by default when exporting?
Is there away to turn this setting completely off?
Sometimes after I'm done exporting my work, I have to go back and re-export the files again because I forget to click Selection Only.

Possible duplicate of Is there a way to save preferences for import/exporters?

That's actually pretty possible and only becomes a problem when you install a new Blender version.
In your installation directory, you have the path:
scripts\addons\io_mesh_stl\
In that folder, there should be the .py files concerning stl import/export.
__init__.py

is the one to open and mutilate.
In line 166, I find:
use_selection = BoolProperty(
        name="Selection Only",
        description="Export selected objects only",
        default=False,
        )

The only thing you need to do is to turn 'False' into 'True' and you should have your checkbox filled by default. The same way you can adjust any default setting. Endless possibilities.

That worked :) you are the best.


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Blender Laggy windows 8.1 Desktop
Title says it all, why the heck do I need to explain this any further with 30 characters??? Hi, I had this program installed on THIS Exact same system and OS Before. Had to re-install the OS and installed Blender and it runs like crap. I used the Opengl32.dll file to get it to work. Before it said that it was trying to get 48000 mhz and got 44000 mhz instead! That has nothing to do with the sound. I have installed and reinstalled all my drivers no avail. Is there a registry tweak that I can do or something????? Plz Help. PS, I do NOT have the ability to make Blender run with Integrated Graphics since I am on Desktop, please no answers for that I will report you.... thanks...

NVM found the Answer! It turns Out I have a UI mod that Mods the Appearance of my user interface in windows 8.1 called Windows Blinds. I check the box in that program to ignore blender and do not skin it. When I did that, the black metro skin that is on the border of all my windows disappeared and reverted to a windows 7 skin. So for those of you that run programs like windows blinds that changes the appearance of you desktop, make sure you exempt blender or it will interfere with blender!....

and on that EXACT same setup it worked before...? and who is NVM?


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Some vertices are hidden in edit mode (not using H)
Some vertices are missing in edit mode as you can see in the yellow circles on the image. I did not press H to hide them. Why are they hidden?

Did this solve your issue? If so, please consider accepting it.

This is because you have a Subdivision Surface modifier. They aren't really missing, it is just the surfaces being smoothed over those vertices, hiding them. You can either disable the modifier in edit mode:

Or you can toggle Limit Selection to Visible:

Here is an example:

Or you can try the button to the right of Novice's first one: it displays your lines as surface fitting curves instead of a cage. Personally I findthat it only makes a significant difference when working with a rather sparse mesh; for something as dense as that face it will probably look/act the same almost everywhere .


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Scaling in object and edit mode
My question is: why do Object mode scaling and Edit mode scaling seem to be incompatible?
I'm quite new to blender, so I may not know sth important about these modes.
The actual case is:
I create a cube, which is 2×2×2 metres in metric units by default
(it's also shown under 'dimensions')

Then, with the cube selected, I switch to Edit mode, and enable 'Edge info: Length' under 'Mesh display'

And it shows the cube's measurements, which are 2m on each edge.
Now I use the scale tool in Edit mode, making the edges 2.244m

That's good so far. Changing back to Object mode, the changes can be seen under 'dimension'

However, when I use the scale tool in Object mode, the scale and dimensions also change, but changing back to Edit mode, the measurements shown remain the same

So the question is, why does the scale tool work differently and have different effects in Ojbect mode and Edit mode?
Also, how can I enter the desired size of my cube manually to get an accurate result, without using the scale tool in Edit mode, and without changing the scale ratio in object mode?

scaling in object mode you are scaling the local space of the object ( also stretching the object to keep the verts in their local  pos ),  you are making 2 m in local space equal 3m in world space (but it still 2m ) , apply scale should help

Related: http://blender.stackexchange.com/q/12288/599

This is how you set dimensions in edit mode manually: https://blender.stackexchange.com/a/68678/28015

The object-mode scale is a property of the object; it doesn't actually do anything to the mesh, but rather affects how the mesh is going to fit in the scene.
Scaling in edit mode actually moves the mesh around; it's equivalent to selecting and carefully moving vertices around to make the mesh bigger or smaller.
There are many situation where you don't want to touch the object scale (e.g. physics simulations tend to get mucked up).
If you have changed the object scale, but really meant to scale the mesh, you can "apply the scale" (i.e. apply the object's scale to the mesh, and set the object scale to 1) by ctrla and select "scale" in the popup menu.

thank you, and how can I enter accurate measurements manually?

Blender probably isn't the best tool for that sort of modelling (although there may be plugins out there to help with it). To try it though, you might find it useful to hold the shift key while doing the transformations - this is used for more precise tweaks.

there is a picture of a magnet in the 3d view header if you enable that button you can choose snap to settings to the immediate right. I find snap to increment,edge, or face all very useful

@Tom Like this: https://blender.stackexchange.com/a/68678/28015

I am not sure if it was explained well yet. Each object has a bunch of properties including properties to delineate it's dimensions, location, rotation, vertices positions, etc.
Changing any location, rotation, scaling and dimension property in object view only changes the property of the object that effects it's relation in the scene compared with other objects.
Changing any location, rotation, scaling and dimension property in edit view only changes the property in reference to the objects origin/pivot point which directly affects it's relative scene data.
So for example:
Scaling an object in object mode by increasing it's size 10x (hotkey s10) will make it look 10x the size in the scene and if you look at it's objects edit mode length's they remain the same
Whereas:
Scaling an object in edit mode and selecting the whole object (hotkey a) and scaling it's size 10x (hotkey s10) will effect the dimensions you see in edit mode as well as the dimensions in object mode since the actual object is 10x larger and should be reflected so in the scene.
This brings about a reason why people reset the object scale to 1x at various points in there project with Ctrl-a applying scale and rotation. Knowing that resetting the global scale (scene scale) to 1 in the X, Y & Z planes will make an object understandable from a users perspective.
Example 1) I model a 3d car and look at it in the scene. Normally you would want it's scale set to 1x so you have a simple relationship to other cars in a scene.
Example 2) It can make calculations easier. Imagine animating an FFT for spectrum analysis of audio waves. You can have an X base of 1.35 units, Y base of 35.56 units and Z base of 3535.5 units on an object you plan to animate and you want to move X in relation to Y in a 2 to 1 ratio. Debugging oddities is simpler at the lower branched levels of mathematics.


text:
How to randomize position of multiple objects?
I would very much like to recreate a workflow I commonly use in Cinema 4D, which is this:

Duplicate multiple instances of an object using the Mograph modifier (similar to the Array modifier)

Randomize the offset/scale/rotation/etc of all the duplicated objects using a Randomize effector

From my search through various Blender forums there doesn't seem to be an elegant way to do this.  In C4D this is such basic functionality that I just refuse to believe that there isn't a way to do it in Blender.
Would love a good workflow to achieve this.

You want to randomize an object that has a array modifier?
For that first apply the array modifier then in the Search bar which appears by clicking Space Bar (if not , in the preferences , you need to change the way space bar works , its possible your spacebar plays the animation) , search for separate by loose parts and select it.Then search for randomize transforms(make sure all the objects i the cluster are selected) and then open the box in the bottom left and change the location ,rotation and scale

THIS!  I appreciate all of the other solutions, which all have their own distinct and relevant applications for different use cases... but this is exactly what I was looking for.  It unfortunately takes away the procedural approach from C4D (in other words, I can't remove the randomizer with one-click) but it stills gets me there without having to using a long winded particle system approach.  Cheers!

In Blender 3.0, searching for "separate by loose parts" doesn't find anything.

Maybe a more Blenderish way is to think of your array as a particle system from the get-go.

All Physics, velocities, etc, switched off. Gravity switched off in the Force Fields panel.

Emission: All on frame 1. Here, from volume, but could be faces or vertices of an emitter, for more specialised distributions.
Source: Grid will give you a regular array. (The Random setting here will randomise the locations.)
Render: .. as Object, instances your source object. Here is where you can randomise scale
Rotation: Here is where you can randomise the rotation of the instances.

Not shown: Viewport Display, where you can hide the emitter in the viewport, by setting As Render, with Show Emitter unchecked in the Render panel.

The cluster on the left: the grid. On the right: after randomisation.
You can name and save the particle settings for future use, you don't have to go through all the settings for every collection. The particle system is in the emitter's modifier stack; it can be 'applied'. The particles can be converted to real instances, there.
The system could be subjected to various force-fields for flow-like distributions, etc. and frozen by conversion at any point.

Yup this is one is definititely better and gives more control ! :)

@Gorgious... welll.. :/   it's not so easy to get a nicely distributed fixed-count array in the fist place, if that's important.. your way's better for that.

This one is convoluted and you don't have that much control but it's procedural.
Create a triangle and add your array modifier(s).

Select the object you want to be arrayed, parent it to your triangles with CTRL + P or Object > Parent > Object (The triangles must be the parent object, not the other way around)
Select the triangle, go into the object properties and select instancing on faces. Uncheck "Show instancer" so you get only your desired objects. Check "Scale by face size", important for later.

Now you can't select your objects in the 3D viewport but you can still select them in the outliner.
Add a displace modifier, and a new texture. Set the direction to X (or Y) and click on that button to modify the texture :

Set it to clouds, and go back to the modifiers. Increase the displace strength to get a random scale.

Add another displace modifier, and another texture. This time set it to "RGB to XYZ". Change the new texture to "Clouds" and the color from "Grayscale" to "Color".
Go back to the modifiers and change the displace strength to get kinda random location and rotation :

Result with an array along Z and a shader :

Also see https://youtu.be/Nlqjfj1lL5A?t=1688 for fine control if you can use the latest alpha version

Got there first.. my version wouldn't have been so jolly.  Do you have any idea when Blender is going to get shot of its legacy texture system? I'm hoping that will be part of Everything Nodes.

I wouldn't know for sure but I don't think it is very high in the priority list so I wouldn't count on it very soon... Personally I would much rather prefer custom shaders for Grease Pencil objects ! But this kind of hack will definitely see an end once the current Geometry Nodes project gets a bit more beefy :)


text:
Cycles uses processor as compute device
My problem is that my graphics card is not available in the compute device option:

Instead it shows my Intel Core 2 Duo, which is my processor. Already set CYCLES_OPENCL_TEST=ALL and CYCLES_OPENCL_SPLIT_KERNEL_TEST=1
My Specs
Processor: Intel Core 2 Duo E8300 @2.83GHz
Graphics Card: AMD Radeon HD 6670
Graphics Card Driver: AMD Radeon Software Crimson Edition
OS: Windows 7 64bit

This should help: Enabling GPU rendering for Cycles

No it is not duplicate.My problem is that my GRAPHICS CARD IS NOT ON MY COMPUTE DEVICE OPTION

@DanishDanial339 That's exactly what the other question is about. Have you tried all the steps outlined in the linked question? If so, please edit your question and tell us what you've already tried and/or any details on what didn't work (errors etc.)

did you look at the image

@DanishDanial339 Are you using the latest proprietary drivers for your GPU?

What OS are you using? That makes a big difference. For example, the open-source drivers for AMD cards on Linux don't support OpenCL - you need the proprietary fglrx driver.

I am using windows 7 64bit. Gpu driver: AMD CRIMSON EDITION.

The HD6670, and other older Terascale-based cards from ATI/AMD, are not supported for GPU rendering with Cycles.
We only support graphics cards with GCN architecture (i.e. most HD 7xxx and above).


text:
How do I change the Copyright information on a rendered file before rendering?
I was looking at one of my render outputs (from blender render) and when I looked in more info (on OSX), I saw something that caught my eye.

How do I make it so that I can change that text in Blender before rendering? I'm using Quicktime with H.264 output but was wondering if I could do this with other video output types. I'm assuming python is required.

You can always render it out as a PNG sequence then bring it into another program to render it out as a QT file.

@icYou But my question is to do it inside blender. I know that I can do that outside but it kinda dilutes the challenge, and won't work for my situation, which is to distribute a blend file publicly that will have my copyright info in it which would be transferred into any exported media.

Looking at the Blender source code, the copyright seems to be hard-coded with the line:

[qtexport->movie setAttribute:@"Made with Blender"

For this reason I don't think the copyright message is configurable via the interface nor via Blender's Python API, meaning the only option is to edit the copyright manually after rendering or see if you can write a Python script to do this (which would be a question for StackOverflow) and get it to execute automatically after rendering with an app.handler.

So I cannot like "inject" this into the blend file. Is there any other way to inject metadata into a blend file only for it to pass onto the rendered output?

Not as far as I am aware. Anything like that would be done with the Python API, but I can't find anything that would allow that.

Well this is intended to add an author attribute to the blend file along with anything exported from it. How about the metadata function under the render tab where it says notes. Would that be transferred onto the movie file? I know it works for individual jpeg and png image files.

Yes, it would be transferred onto the file, but you may need other tools to be able to read back that metadata as opposed to seeing it in the window in your screenshot. See: http://blender.stackexchange.com/questions/48700/find-blender-png-or-other-format-metadata-in-adobe

For the image outputs, I can see the metadata straightaway by opening it in a text application and looking at the compiled mess. No problem. My real issue is if the metadata option applies to video outputs because I tried looking it up in the compiled mess of the mov file and found nothing.


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Make Human Import
For some reason, I am unable to import a Make Human model into Blender without losing the texture binding and their settings. I have been following this video and when importing my model into blender, there are no textures. Can someone help me?
What I did was, make a model in MakeHuman. Then I exported as a Dae file without changing any settings. I opened up Blender and imported the Model using the default settings. When I render it, the model has no textures.

Fixed the problem. Apparently the Textures must be in the same folder as the .dae file itself, and won't work if they are in a sub-directory.
So just drag all the textures to the same folder as your .dae file is in, delete the now empty texture folder (if you want) and now you can import the COLLADA into Blender.

This by the way is the most common problem when importing models from other sources into Blender. If the Textures won't show up just drop them into the same folder or reassign them.

I highly recommend export with mhx2 exporter in MakeHuman and using mhx2 importer in Blender. This work fine and is developing exactly for using with Blender. Why you make your life more complicated using 3rd party format?
Or you can make new materials using exported textures manually. UVs should be right.

The MHX2 file format is a third party file format. You have to manually download and install the makehuman and blender addons which you can find here

It is primary developed for import rigged meshes from MakeHuman to Blender. It is developed by MakeHuman developers, only in other project. Dae is devolepded by Sony. Sony has nothing with MakeHuman or Blender. So what is and what is not "third party" software? :-) ;-)

The projects may share developers but it is not part of the makehuman or blender development - as an external project it falls into third party. If it was an official format it would be included with the official makehuman releases. Either way we have to download the addons and install them for both programs.

OK, you are right. "3rd party" was not accurate expression in this case. But please don't play with words. :-) The point is that mhx2 is develop exactly for situations like this and for that is better using it than using any "outside" format. I thing we can agree :-)

The thing with the Dae export is the UVs are already right. So there is no need going through the hassle to download a program, download a plugin (which I actually did when I was trying to find a way to get the textures to show up) to make it work. Anyways isn't mhx deprecated in the latest version of makehuman?


text:
Characters Move Independently In Single Text Object
Objective

To use a single text object where each character of the text moves in their own unique manner.
Detail

I want to be able to use one text object to create an animation where characters move onto the screen one by one. The way each character moves onto the screen is slightly complex, so I want to premake it myself for the rest of the unknown number of characters to follow. I also want to set the delay between when a character starts its animation and when the next character starts its animation.
The reason why I only want to use only one text object is because the amount of characters that are being animated are unknown and can vary. Additionally, I want to be able to press tab to edit the text and type it in with ease where it will automatically determine how the characters are going to be animated based on the presets that I made (the animation path I made for all the characters to follow at different times and the delay between each one).
Normally if I wanted to have the characters move independently, I would need to separate each character into their own text boxes and manually copy the animations. This will be troublesome if the entire length changes.
Additionally by putting each character into their own text objects, it would be hard to judge the distance between each character (and imagine if I have to change the text).
By changing the length of the single textbox, it will also change the amount of characters needed to animated. This will also change the amount of time need to finish the animation. However blank spaces will not add any time as they have no animation and will be skipped.
Final

So can someone please help me and show me how to do this in Blender Render. It may involve Python and although I have learnt a little bit of Python a long time ago, I have no clue of how Blender interprets them and it's libraries so bare with me.

Do you want to a completed solution or ideas so you can create your own solution?

@atomicbezierslinger well you told me how to assign locations of each character but I still do not know how to assign some keyframes to the characters through script.

Many animations have a technical aspect and an artistic aspect.  I was providing some technique suggestions to you. You must control the artistry.  Blender Objects can exists in groups.  Groups can be selected on a certain keyframe.  Then insert keyframe.  Perhaps I do not understand your written words.  It would be best to change your question rather than create a long comment section.  This question does not seem to be generating much external interest.  I will probably drop the answer.

@atomicbezierslinger I'm not asking about having you do the artistic aspect. I'm just still confused how to add in my artistic aspect into the technical aspect.

Image above showing extents of individual characters in a single Blender Text Object.
Some miscellaneous points.

For ease of expressiveness, in the not quite so long run, I suggest you animate either single letter text objects or the mesh converted objects.
You may want to search for a script which already does what you want.
Text can follow path as a whole quite easily.  Having each character follow a different path requires more work.  Link for various approaches ...How-To: Text Sliding out of a Circle 2D
Your statements lead me to believe you want characters following individual paths.

In the image above we see the Blender Python Console window.  We have probed the location and dimension of a text object.  You see the X-axis value increase as I add letters.  Subtraction required for individual character location perhaps other considerations.  I have not found a more abstract probe for individual substrings of a larger string.

In the image above is a text editor window with an executed script.  The blue balls have been placed at right side x axis of each letter.  Thus the script has some reasonable knowledge of extents in the x direction.  You can store the measurements in a Python list if that suits you.
Inspect, Verify and Improve the script.
Know that text character placement may not be as easy as placing a cube.  Text characters have their own sense of orientation and aesthetics.  Baseline for example.  If you separate characters of a text object take care to notice any adjustments to the individual origins.
If you have final placement of the single objects whether text or mesh you can keyframe those positions as final positions.  Then your animation can occur close enough to those final positions.  For example a path which gets close enough to your final position can ease out its influence.
There is more left for you to discover.

Wow there's a lot for me to learn. In the last image, did you place the balls on the right end of each character so that later on I can determine the locations of each characters and know the uneven distance between each one?

Also what does redraw_timer do?


text:
Automatic bump mapping

In the image, I know that setting Normal to a value (other than 0) in geometry will create a bump map from the texture onto the material. It works well and I'm doing this for the hair of a human model. What is the difference between positive and negative? Does one bump in one way and the other the exact opposite? (So if 1.0 bumps it outwards by a certain amount, -1.0 bumps it inwards by the same amount).
But my main question is the Bump Mapping Method and Space. What do these do exactly? I looked up on here and it doesn't specify their purposes, only shows the available options. What is the difference between these options? I found that Original method (which will for some reason disable Space) looks the best to me but I want to make sure that option is the most appropriate for the situation I am in.

No one figure it out yet?

I did ORiginal and it broke. I did highest quality and it was the highest quality.

For space, check out http://wiki.polycount.com/wiki/Normal_Map_Technical_Details .

As far as I see, if normal is positive light colours bump outwards and dark inwards, if negative - the other way round.
The rest doesn't seem easy, but here are some links. I think "Method" is mostly about quality:
http://kishalmi.servus.at/3D/bumpcode/
"Space" should tell in which space the normal vector will be stored. But the results look strange.
Anyway - why not use cycles?

I know cycles is much better but it seems too complicated and different. And I don't have much time to learn.

The thing I'm scared about space is I'm afraid it will make the bump map be projected from another object, thus if I move the hair, it's bump will change, which is not realistic.

Cycles is not too complicated (although it is different). Watch this and see what you think: https://www.blenderguru.com/tutorials/introduction-to-cycles/

For "Method', select the quality level you need. For realtime, 'Low quality" is much faster than the higher ones. "Compatible" (for me) does not do anything. I think it's a fallback option for old Blender versions.
The "space" dropdown, afaik, is only relevant for normal maps. This is why it's greyed out.
For the "normal" value, you may want to try very small vaues like 0.05.


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How do I create an 8 sided die from one object?
Simply put, is there a way to make a cube balance solely on one point/vertex?
I'm struggling. I do not want to have to join two objects, nor have to extrude an object. I just want to have a simple eight-sided die created with one mesh.

If you look at these google image results, you will see that it is simply two pyramids joined at the base.

I know, but I don't want to join two objects, because I've had a lot of problems with that in the past.

You can add a cube, go into edit mode, add a loop cut (ctrl+r), and merge the top and bottom faces into one vertex. I can post an answer

That shape called octahedron, you can bevel the cube with a value of 1 and remove doubles.

A cube balancing on one point is still a cube and it still only has six faces.

@DavidRicherby Cube has 4-sided faces, and octahedron has 8 faces

@Denis Yes, and a cube has six four-sided faces. But the question header asks for an eight-sided die and then says, "Simply put, is there a way to make a cube balance solely on one point/vertex?" I'm pointing out that a cube balancing on one of its vertices is not a simple eight-sided die because it still has the same six sides it had when it wasn't balancing on a point.

oops, thanks for correcting me people! derp

Start by adding a cube, entering edit mode, and scaling the whole thing on the Z axis by 1.5 (depends on desired result). Now that you are in edit mode, press Ctrl+R and click to add a horizontal loop cut. You can now select the top and bottom faces and merge them into one vertex each to make the point (select verts/faces/edges and press Alt+M > At Center).

The precise Z axis scaling factor you need, in order to get a perfectly symmetrical octahedron with this method, is sqrt(2) ≈ 1.4142.

@IlmariKaronen Exactly. I think I accidentally used 2 in my GIF example, thus the scaling

You can create an Octahedron from a cube, that is its dual polyhedron:

Add a new cube, then in edit mode select all using A button.
Hit Ctrl+B, input value 1 and hit Enter.
Hit Ctrl+V and select Remove Doubles.

Thanks! That's quite useful if you just want an even octahedron

Wow!!! Ultra fast method!


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Game Engine animations not working?
I've created the animations, and everything is working except when I press Shift+W to sprint. My character plays the animation, after I release keys and play something else like walk it also works, but after that it stops working, and none of the animations will play besides the Idle animation.

did you already fixed this? please expand the action nodes so i can take a look at it. did you made this 3D model yourself?


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Video with unusual frame rate will skip or repeat a frame
In Blender, I overlaid a video onto the camera using background image to help make an animation (my objective is to copy the video). Unfortunately it has a very unusual frame rate. I have matched the animation's frame rate with the video's but sometimes the video would skip a frame and repeat a frame. Does anyone know how to fix this?

@cegaton I reinterpreted the videos unusual frame rate to a more common value and it is now normal. I think changing the animation frame rate does nothing.

I use a Workaround...


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Blender Render: Python material
How do I use python to set keyframes for the diffuse colour of materials in blender render. This is what I got, but it doesn't work.
mat = bpy.data.materials("Abc")
mat.diffuse_color = (1.0,0.0,0.0)
mat.keyframe_insert("default_value", frame=scene.frame_current)

I have an existing material that I want to set keyframes for, but I don't know how to do it. I tried searching it up and only saw python scripts for cycles materials.

I found out what I did wrong. The documentation of materials on the blender api page did not mention "get", but the bpy_struct said you can use "get" in the function, so:
mat = bpy.data.materials("Abc")

Should be:
mat = bpy.data.materials.get("Abc")

Also I have to define what scene of scene.frame_current is.
That means at the beginning, I need to import bpy.
import bpy
scene = bpy.context.scene

Also default_value is nonsense to be placed there. Being the diffuse color that's had its keyframe changed, it should be:
mat.keyframe_insert(data_path="diffuse_color", frame=scene.frame_current)

In conclusion, it should look like this:
import bpy
scene = bpy.context.scene

mat = bpy.data.materials.get("Abc")
mat.diffuse_color = (1.0,0.0,0.0)
mat.keyframe_insert(data_path="diffuse_color", frame=scene.frame_current)

You don't have to use get() the material name is a dictionary key so you can use mat = bpy.data.materials["Abc"]

oh. I didn't know that. Are they the same though?

The beauty of get is collection.get("doesnt exist") returns None whereas collection["doesn't exist"] will return an error.  IMO  if mat is not None: is more elegant than a try except clause, or if "doesnt exist" in collection, hence I use get(...) as a matter of practice.

ah! then im fine here.


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MakeHuman Inverse Kinematics
I have a makehuman model that I want to use for animating. However, with the current forward kinematics, it's very difficult to animate each bone one by one. So after messing around, I figured out how to use inverse kinematics. However I'm having trouble making the legs calculate their rotation realistically.
The legs when I did the IK looked like this:

The problem is the legs aren't turning on the Z axis so that the foot faces the direction it is at. It only really utilises the X and Y axis. How am I able to make it so that it can only move on its own local Y axis (which is based on its own rotation) with that rotation controlled by the Z axis?
The end result should look something like this.

This is what it currently looks like:

Note how from the top-down view, the foot is not facing in the same direction from the leg bone. Its angle is very off.

No one can figure this out? Maybe pole bones would help?

It looks like you have too many IK constraints on your legs and arms. You should have just on per leg or arm (on the shin or forearm bones) and then set the targets to the foot or hand, and the chain length to the number of bones in the leg arm. To avoid bending on the twist bones at the top of each arm/leg, you will need to adjust the settings to lock particular axes on the bone ik panel in pose mode.
See https://www.blender.org/manual/rigging/armatures/posing/bone_constraints/inverse_kinematics/introduction.html

I realised my problem. The helper bone is not meant to be attached to the leg bone. It should be parented but not connected, and the helper bone should move further outwards to make the leg point as expected.


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All textures upside-down
I imported a large scene of Wavefront .obj format and I discovered that every texture in the scene is upside-down. Is there a way to import the textures properly or flip everything on the Z axis? If I have to use Python, how do I change the size of every texture to flip it. Everything is UV mapped.

And i prefer not to flip the textures from the image files themselves.

Could it be that your faces are flipped? Try recalculating the normals.
to do this you can press 'N' while in edit mode.

Another solution to get the correct mapping is to select all while in edit mode and then press 'S' to scale and type in -1 on your numpad.
The reason why you should do it in edit mode and not object mode is that this way your object still has a scaling value of 1 instead of -1

Well I would have to combine all the objects and do that.

I don't think you need to do this. Could you post some screenshots to your question? This would be easier to comprehend the scene.

In python it's not very hard : http://web.purplefrog.com/~thoth/blender/python-cookbook/flip-texture-v-coordinate.html
import bpy
import bmesh

def mission1(mesh):
    bm = bmesh.new()
    bm.from_mesh(mesh)

    for uvt in mesh.uv_textures:
        uv_layer = bm.loops.layers.uv[uvt.name]

        for face in bm.faces:
            for loop in face.loops:
                loop[uv_layer].uv[1] = 1-loop[uv_layer].uv[1]
    bm.to_mesh(mesh)
    mesh.update()

if bpy.context.mode != 'OBJECT':
    bpy.ops.object.mode_set(mode='OBJECT')

meshes = set()
for obj in bpy.context.scene.objects:
    if obj.select:
        meshes.add(obj.data)

for mesh in meshes:
    mission1(mesh)

Just select all the defective meshes and it will flip the V coordinate.

Uhm. Select the faces that are upside down (all, as you say in your case) and in the uv mapping editor, select all by pressing A, then press R and rotate it by 180 degrees. If something goes out of bounds, press CTRL+P

Just one lil problem. They're different objects. And it would be quite difficult to combine everything and seperate correctly.

I would try to mirror all UV islands like this.
Join the models or use MultiEdit addon and enter Edit mode.
Select all and open UV editor. Switch pivot to Individual origins and mirror all by CTRL+M and X or Y.
Then separate models or exit from MultiEdit edit mode.
If it doesn't work for you, upload the model here and I will take a look at it.


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Corrupted? Plane with White material rendering Black in Solid view
I have a collection of planes with different designs and changing their material isn't reflected in solid view in both blender internal and cycles render view. The materials I'm trying to use have been working fine for other objects.
All the planes have once been set to a pure shadeless black texture, and have had a Solidify modifier applied to them. The rendering isn't fixed after removing the modifiers. Flipping the normals doesn't have any effect.
The vertices of the planes act weird. If I add an edge, one of the triangles will be colored according to current material. If I then dissolve the new edge, it will also delete the points, even though they should be connected to the other points.
Dragging a point so the plane is self-intersecting will cause the material to display properly.

Also, the plane is rotated along the Z axis. If I Scale the plane (in object) by 1 (or anything), it will automatically align itself along the X axis (the way it previously was).
I tried to rebuild the points of the plane, and I'm not able to align/snap points to the vertices of the plane in edit or object mode. Also, I can't split the plane using the Knife tool
Currently, the only solution I have is to trace the planes.
Blender source file containing some of the planes.

You should include a source file. It helps to get your question answered more quickly.
The problem could have multiple options to fix the issue so I'd definitely recommend posting your .blend

The problem is you need to apply your scale transforms on the objects. The reason the faces are shading poorly is because of Z-fighting, which is occurring because your objects have zero Z scale value. Applying scale will also allow your modifiers to work.
To apply the scale, select all your objects in object mode, press Ctrl-A and Scale. Or in the viewport header, Object -> Apply -> Scale
Your scale values should now read 1.0, 1.0, 1.0.


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Is there a way to add a custom Pie Menu in 2.8?
Is there a way to make a custom pie menu in 2.8? I'd like to add one for switching between trackball and turntable navigation. It gets very annoying going into preferences when you just want to use trackball for sculpting and turntable for other things.

there are two ways to add custom pie menus.

get the Pie Menu Editor addon (paid).
code it yourself, its not that difficult, you can use my pie menu addon as a starting point, if you have never coded you might want to learn about python first or just copy the code below and put it in a file that ends with .py go to the Add-ons tab and click install, chose the file that you made with the code below.

This is a basic addon that should do the job, the default keymap is Ctrl + D
import bpy
from bpy.types import Menu

bl_info = {
    "name": "S.Simple Pie Menu",
    "author": "Syler",
    "version": (0, 0, 0, 1),
    "description": "Adds Pie Menus",
    "blender": (2, 80, 0),
    "category": "3D view"
}

addon_keymaps = []

def add_hotkey():

    wm = bpy.context.window_manager
    kc = wm.keyconfigs.addon

    if not kc:
        print('Keymap Error')
        return
    # object Mode
    km = kc.keymaps.new(name='Object Mode', space_type='EMPTY')
    # here you can chose the keymapping.
    kmi = km.keymap_items.new(
        VIEW3D_OT_PIE_template_call.bl_idname, 'D', 'PRESS', ctrl=True, shift=False)
    addon_keymaps.append((km, kmi))

def remove_hotkey():
    for km, kmi in addon_keymaps:
        km.keymap_items.remove(kmi)

    addon_keymaps.clear()

class VIEW3D_MT_PIE_template(Menu):
    bl_label = 'S.Menu Navigation'
    def draw(self, context):
        print("test")
        layout = self.layout
        prefs = context.preferences
        inputs = prefs.inputs

        pie = layout.menu_pie()
        pie.prop(inputs, "view_rotate_method", expand=True)

class VIEW3D_OT_PIE_template_call(bpy.types.Operator):
    bl_idname = 'sop.sm_template'
    bl_label = 'S.Menu Navigation'
    bl_description = 'Calls pie menu'
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):
        bpy.ops.wm.call_menu_pie(name="VIEW3D_MT_PIE_template")
        return {'FINISHED'}

def register():
    bpy.utils.register_class(VIEW3D_MT_PIE_template)
    bpy.utils.register_class(VIEW3D_OT_PIE_template_call)
    add_hotkey()

def unregister():
    bpy.utils.unregister_class(VIEW3D_MT_PIE_template)
    bpy.utils.unregister_class(VIEW3D_OT_PIE_template_call)
    remove_hotkey()

if __name__ == "__main__":
    register()

If i interpret this code correctly
What ur doing over here is that u create a menu and call it using the operator which u in turn call it a through a shortcut (keymap)


text:
Why is vertex drawing ignoring grid snap settings?
If I want to draw some vertices on the ground plane, I seem to have to place the first vertex with Ctrl+RMB (not Ctrl+LMB as the manual states), then Extrude the rest of the vertices using E, which is fine, except that using Ctrl+RMB seems to ignore my snap to grid settings (using E behaves properly), so I can't accurately place that first vertex.
Is there a way of making that snap when it's placed, rather than having to move it afterwards using Blender 2.8?

If I want to draw some vertices on the ground plane, I seem to have to
  place the first vertex with Ctrl-RMB (not Ctrl-LMB as the manual
  states...

That's probably because Blender used RMB for selection by default prior to 2.8. WWas it on the 2.8 manual or the 2.79?
For your issue you have to extrude, cancel the moving of the extrude by using right clic mouse button, then move it with G (dont deselect anything by error) to get the snapping effect.