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Array + Curve modifier with irregular Spacing
I'm currently working on a rollercoaster track generated from vendor data. I imported the curve with a python script and I'm placing the track elements on it with two objects, one for the tubes and one for the ties. Those elements are then array and curve modified.

On my curve (which comes from the original track data), each point represents the position of a track tie.
What I need to achieve is to place the ties on the points of the curve, which have non-regular spacing between each points.
Is there a way I can achieve that automatically (or at least without having to move them all by hand) ?
Thanks.
Edit: I also need my ties to stay perpendicular to the curve tilt, which also comes from my initial data-set :

My track tubes are set-up with simples array+spline modifiers and they automatically fit that tilt :

Edit 2 : Here's a simplified .blend file.
https://we.tl/t-6x8JN5OjzX

you can do it with geometry nodes like this:

Note: For your case you won't need the resample curve node. The geometry nodes modifier is added to the curve in my example.

update:
if you want to "align" the rotation of instanced objects to the curve you can use this node setup:

** UPDATE **
try this setup here:

result:

I know, in the beginning/end, there is some weird rotation. But this might be caused by your curve...so you should check your curve data.

This will need a bit of tweaking (rotation) but it works ! Many thanks :) Is there a way to apply the curve tilt to the ties too ?

i updated my answer. If it helped you, please click the checkmark left to my answer. thanks.

Thanks @Chris, however it isn't able to match the curve's "tilt" (each Spline point has a p.tilt property which I can inspect in edit mode by pressing n) property with that setup. I updated my initial post with a screenshot of what I'm talking about

Can u provide blend file so we can try out?

Just updated my initial answer with it.

i updated my answer

"in the beginning/end, there is some weird rotation." yeah that's the issue I'm encountering too, and it's certainly not from the curve data as the tubes are following the exact same curve. I've plotted my datas on excel and they're really smooth and coherent. I'll have to dig a bit more into this. Many thanks for your help :)

Also just noticed there's a Curve tilt node. Seems to get closer, maybe now I just need to tweak the Align Euler To Vector node and hopefully it will be good !


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Real Snow add-on has coloured snow in some areas
I'm creating a simple winter scene, using the real snow add-on to make realistic snow. However, when I render the scene, the top of the snow appears to have some weird RGB colour effect (less noticeable due to the Denoise algorithm enabled). The only thing I changed with the snow is the roughness from 0.1 to 0.6.
The Blender version is 3.3.

Snow shader editor:

If I had to guess, I'd say it probably has something to due with the Subsurface Scattering values (perhaps the subsurface radius RGB values are set to favor blue/cyan for snow).

I just added the image of the shader editor.

I'm not sure then - the colors favor blue but only slightly. Other than that, a Subsurface value of 1 is generally considered very high - maybe try lowering it? (around 0.2-0.3 is considered a common starting point)

That seemed to help, so thank you. I hope it gets patched soon enough!

source: Stack Exchange

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

sort: votes


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How to remove shapes in viewport rendering 2d animation?
When I am playing the animation in viewport mode I can see these blue and green shapes that show the previous and next keyframe. How can I
I would also like to hide the lines of the stroke coloring that show around the character. How can i remove these?
Both things I want to remove are marked with blue arrows.

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

The solution is to disable onion skin and edit lines from viewport overlays

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

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


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Transparency issue for images with alpha infront of GP in render?
I am trying to do a 2D animation and would like to have an image plane in front of the gpencil drawing.
A solution I found online was setting the plane's setting in material properties as Alpha clip, that helps in viewport rendering but not in normal render (ctrl + f12).

You should adjust your Question, the issue is not missing image in render, but transparency issue for images with alpha infront of GP in render. Thank you

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.


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Why is a text not rendering with glow effect but other objects are?
I have a project I'm stuck on, it has text and a grid effect (made from a plane) for the floor. I need all objects to have a glare effect emitting light, everything is glowing correctly except one text item, the blue "Media" text. I have added emission the same as the other items and i think done everything correctly in "compositing nodes"
As you can see the pink grid is rendering a glare as is the other texts not shown but the blue "Media" text will not render any glare/emission.

I've noticed that the other texts and the grid are all showing a "Particles" tab so I've missed something somewhere. That's the only difference i can find between the ones that glare and the Media text. Still really new at this. Spent hours trying to work it out. "Media" text is supposed to be glowing like everything else.Thanks!

Update: I think i have narrowed down the problem but have no idea how to fix.
I have a long list of different materials as pictured,the material i;m trying to add to the "MEDIA" text is not giving emission, I've noticed it has a 0 in front of it. So i tried using the other materials and some seemed to work and emit light so i thought great i'll just change to the color i want. However, that doesn't work, when i change the material color at all it stops emitting on rendering.Or if i make a new material for the "MEDIA" text it wont emit i can only add an existing material but not change its color.Would like to use a color i choose, any ideas?

Update:
Blue on text will not emit light in rendering

All i did here was change color from blue to a different shade or completly different color, kept everything else the same and it would render emission.

Your Text.008 seems to be an actual text object, while Text.005 has been converted to a mesh. It could be that the Transparent BSDF into the Volume Material Output doesn't play well together in this case (perhaps that kills the emission intensity?). Could you try to convert the text to mesh and see what happens?

Hi, Just tried converting, that didn't seem to work. I have other text items that emit ok and they too are an actual text item not mesh.

i've removed the Transparent BSDF, still no joy and converted text to mesh, it says CUTEXT.006

Half year later, but isnt that Glare use to glow according to light intensity, so blue is not bright enough to be calculated for glare? Try to change Treshold value.

I've solved this. Glow/glare is determined by a background (it bleeds out past the object). Text and shapes have no background like a transparent image plane would.
Solution: Add a plane behind your thing that won't glow, and make sure to add it to the object/mesh. Make this plan transparent, and it won't render but it WILL provide the background needed to show the glow. It's a coding thing that shouldn't exists.

I dont think you are right here , on the last two screens you can see there is a background in render view.


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Copying and pasting wrong object
ISSUE:
I am trying to copy an object from one blender file to another, how i normally do this is by copying object(CTR C)from one file, then (CTR V) in the file i want it pasted.
Now when i try doing this despite what i copy,  when i paste it, it pastes an object i didn't copy. Its an object i previously duplicated i think but i don't know how to clear this.Thanks.
picture is of the object that keeps pasting, i need this item cleared from the clipboard or something?

I don't think this is supposed to work. Try the "Append" in the "File" menu. You can append only what you saved in the other file. (Search for object)

Thanks! I tried this and it worked but for some unknown reason it pasted the correct object (helicopter blades) from my other blender file but it attached it to one of my cameras in my scene. Picture above.


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Select Vertices by Material Color
I have a mesh in .obj fileformat which if I render in color looks like this:

I would like to select only the brown/dark colored parts and delete the rest. How can I achieve this ? Is there a select vertices by material color ? Or can I do this differently ?
Thank you very much.

Are you working a obj you created from a  photogrammetry ?
IF so, you cannot. Unless you wanted to do that in an earlier part of the process... Photogrammetry takes the mesh and attaches the texture to the entire mesh. So you cannot separate out the texture by color because they are all on the same texture file... you can split up the faces and then assign them a new texture then delete that texture but at that point you're not avoiding the problem of having to delete everything.
When working with Photo scans you just have to except the fact that you will have to do some busy work. There are programs that can auto fix your typology - which may help in selecting methods ( being able to select and delete edge loops), but other than that you will be working at the geometry level which does not see color-only textures hold that data.
This is a really late reply. However, if anyone sees this I hope it helps.

You could select the material slot and then click 'Select', which will select the faces that have this material. Only faces have material assigned, vertices don't.
You can do this in Edit mode only with thanks to Delagone :)

I'd add that this is only possible in 'Edit Mode'

Thats great. Thanks for showing me this. Unfortunately this does not solve my problem because it selects all the material and not just the brow/black parts. I don't know enough about how Blender stores this information, but somewhere the color must be associated with a vertice and I am wondering if I can tap into that so I can select a certain color range and discard the rest. This would really be helpful for me. Thanks again.

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


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Spin Tool behaves unexpected
I import points from a .csv and connect them with a single line. After that I Spin them 360 degrees/steps. Deselect and Reselect all vertices. Click Remove Doubles. Unfortunately the mesh is not only non Manifold but also the resulting non manifold vertices are not constant. Here a screenshot of the upper part, where one can see that not all of the vertices are non manifold.

I did the exact thing already and it worked the first time. I don't understand why it gives me this error. Any help would be great. Thanks

It could be linked to the removes doubles treshold. Try to increase it a little to compensate computation errors when making the spin. (Not sure the 360° spin will be a perfect 360)

That was it. Thx a million!

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Distribute and Edit Objects along Polygon
I would like to create an object. Multiply it along the edges of a polygon (e.g. pentagon) and then by editing the original object, modify all the duplicated instances. Like a Mirror modifier but not along x/y/z but polygon axis. How is this possible ? Here an image of what I am looking for. The spheres are duplicated along the edges of the pentagon.
Thank you

Use either particle system or dupliframes. Also related - http://blender.stackexchange.com/questions/44353/how-to-add-multiple-meshes-on-the-locations-of-the-vertices-of-for-example-a-s

Dupliverts should do exactly what you want.
I could spend ages explaining it here, but the manual does it better :)
You'll need to turn orientation on to get things facing in different directions.
Edit: But do follow the link in Mr Zak's comment, it contains many further examples and an entire alternative method.  Not sure why it wasn't an answer too.


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Smooth edges on a custom object
I have a custom made object (no simple standard mesh, but nothing complex, see below) and lost a lot of time trying to make the edges smooth.
I tried the bevel modifier, sub surf modifier and bevel by select certain edges (ctrl+B). None of them worked fast and reliable.

Selecting them edge by edge (very time consuming) left me with problems where two different bevels where meeting.
the bevel modifier did no work as expected every time
sub surf modifier just created a very distorted mesh.

This is my mesh (viewed from different angles):

I just want all the edges to be smooth. No big deal...I thought :)
I only succeeded on the front ones.

Did you enable smooth in shading?

I need this as a real object afterwards so shading does not help me. At least as I understand it. Thanks

@user413734, do you want to 3D print it ?

Yes, I just need these edges to be smooth and the rest of the object not distorted.

Try using Bevel modifier with angles enabled as a limit, then apply the subdivision surface modifier

The point is to imagine the several angles your mesh will have to be bent.
It can be composed of an initial shape and 3 modifiers : mirror, simple deform and subsurface.

Here, there is a final curve : the "U" general shape.
But before that the mesh can be flat. Here the mesh before using the two final modifier (simple deform and subsurface) :

The main point is to use quad everywhere so that :

Edges are in the good position to be bend to the "U"
Subsurface modifier works well

Notice the selected line on the screen capture : it is here to preserve the outer edge and avoid the subsurf to deform it too much.
As you want to print it, you may want a "lot" of subdivision.
Here is the modifiers stack :

Here is the blend file

I can't reproduce it. Can you share the blend ? What is the starting form you used ? A cube with rounded corners ? Did you choose a Mirror Object in the Mirror Modifier. Thanks.

Edited to add the file (at the end of the post)

Thank you very much. One last questions how did you add the line that protects the edge. Edge Loops won't work with me becuase it is not a straight line I think. Thanks again.

@user413734, if I remember well, a bevel, Ctrl+B and the some manual adjustments for the extremities


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Joining an Cutting Objects
If I have two object like the two planes in the image below.
And I join these two planes (CTRL+J). How can I cut off the part that sticks out of the bottom of the bigger plane, so this would be level on the ground, without holes. Ideally the bottom part would be one Face (or as minimal as possible). Also the internal edges/faces/vertices where the plane cut through would be ideally not be represented in the model anymore. Only the parts that you can see outside. I know I can clean it up step by step, but I was looking for a more easier, professional way. Since I would have to do this very often.

Related: http://blender.stackexchange.com/q/12311/599 and http://blender.stackexchange.com/q/15687/599

In the edit mode select the face selection mode, select the part of the mesh you want to remove, if it selects both the upper and lower parts, subdivide the selected face after its been subdivided select the part below ground level and click on P key to seperate you'll see an option that comes out click on 'selection' then you can delete the seperated Part if you want


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Cycle Normal Pass in Camera Space
I am wondering if there is any way that we can alter the cycle normal pass to output value in camera space. Currently, as far as I know, the normal is in object/world space, which does not change when the camera is moving around.
I have tried using matcap, but the result is undesired. Matcap coasts a new material on the objects and overrides its transparency (eg. leaves will appear as just a rectangle)
UPDATED: The interest render engine is Cycle, and as far as I know, in Blender Internal, the normal pass is already in camera space. That could be a solution, render the scene twice, one with Cycle and the other with Blender Internal. However, it is not desired since the overhead would be too much.

Which render engine? In cycles you can use the camera view vector or maybe an osl script could produce what you want.

I forgot to mention, it's Cycle. I reckon that Blender Internal's normal pass is in camera space. But rendering 2 scenes (independently) is  undesirable since it would double the time.

@sambler: could you please specify the answer? I can tranform the normal vector using node editor but only for material output, not for rendering (maybe I don't know how to do it). Besides, I have no experience with OSL script, maybe you could help me more?

This can be achieved using the Vector Transform node to transform the Normal from World coordinates into Camera coordinates to match the Blender Internal Normal result.
Use the following material :

The key part is the Vector Transform node - this is set to transform the Normal from from World to Camera space. The remaining nodes perform some necessary conversion since BI appears to map camera space in opposite directions to Cycles - so the X and Y both need to be multiplied by -1 (Z is unaffected).
In order to apply the normals to the whole scene (to create a Normal 'pass') you can use the Render Layer Material Override setting to create a whole layer that renders all materials as this and include that pass in the compositor in place of the Normal.
As a comparison, this produces the following result :
Blender Internal :
Cycles :


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Multiple different terrains type for landscape
I am trying to create a landscape with different type of terrains. Normally, what I would do is to create a big plan for a meadow which has dirt material/texture and grass particle. The meadow has modifier displacement to have hills/valleys effects. On a part of that meadow, I would like to make it look like sand (so no grass, no dirt but sand), or gravel (with gravel displacement modifier and textures), or some other types of terrains. As they are on the same landscape, all type of terrains (dirt, sand, gravel) must be align with hills and bumps that already on the plan. However I do not know how to proceed. One idea is I can create different plans for different type of terrains but then I do not know how to align the plans together to have a smooth landscape (hills and valleys) results.
PS This is a for a close-up view, that's why I'll need really high quality terrains (gravel, dirt), each with real geometry from bump maps in displacement modifier. So low-poly texture painting would not be desired. And it is for Cycles

Thanks for your interest. Currently I have no image (will add if you really need it) because I think it's quite simple to explain in words. I have edited the question to have more explanations.

A solution maybe around vertex groups and vertex weights and using one or more displacement modifiers (vertex group slot). But for a 'close up' view, not sure at all that it will meet the result you want. Could you add an illustration of the final result (some image with similar effect)?

Thanks for the hints. I am not used to vertex groups and vertex weights so it would take some time.


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How to find if a point is inside a CURVE
This question is a kind of follow up to this question How to find if a point is inside a mesh?, just in a different context. That is how to basically apply the same thing for curve objects such as tree sapling or ivy curve (from sapling addon and ivygen addon.
I wouldn't prefer converting curve objects to meshes because of large number of them and doing so could quite burden the system memory and rendering time. Besides, converting takes time if you have to performs point-checking quite often.

Convert (a temporary copy of) the resulting curves to mesh first?

That would work. Just a bit of concern, would it burden the system when you have quite large number of objects need to be converted? And would converting take good amount of time. This is in the context of having so many objects and the point-checking operation is done excessively many times.

I am not experienced with scripting so I can't really be of much help here. I am guessing you would discard said temporary meshes afterwards, so no long-term performance impact would incur. Conversion itself is relatively quick, I think. Maybe loop over all relevant curves first, copy and convert all to mesh, join them into one single large mesh and do the checking only once. Discard large mesh afterwards

Thanks for your suggestion. It's indeed a good idea. Thanks a lot.


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Which cycles rendering pass is antialiased
In all render passes that Blender Cycles support, which one are antialiased and which one is not by default. And, if possible, how can I turn all the anti-aliasing for all of them completely? I got know before that Mist passed is anti-aliasing, Z-buffer is not (correct me if I'm wrong).
Here are the list of the other render passes:
Diffuse Direct, Indirect, Color
Glossy Direct, Indirect, Color
Transmission Direct, Indirect, Color
Subsurface Direct, Indirect, Color
Emission
Environment
Shadow
Ambient Occlusion
Normal
Vector
Object Index
Material Index

What do you mean "turn them all off" ? Do you want to turn off anti-aliasing on it?

Sorry I wasn't clear. I mean to turn off anti-aliasing for all the passes (if they are on by default).

For reference, I wrote an answer here about which passes are antialiased. https://blender.stackexchange.com/questions/67229/to-what-degree-does-cycles-sample-level-impact-other-passes/67470#67470 The answer @Crantisz posted on this question is a good summary of how to bypass AA in Cycles.

You need to know, that there is nonstandard algorithm to get anti-aliasing in cycles instead normal render. Each pass in cycles also is an anti-aliasing pass too. Each pass specifies the color, shadow and antialiasing at same time:

And cycles has a setting to manipulate how far each pixel sample can deviate to get anti-aliasing:

Making the filter size value smaller will squeeze the samples more into the center. So there is no option to turn off anti-aliasing, but you can make filter size at minimum to get similar result:


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convert OpenEXR float to color value
I am exporting a scene to OpenEXR multichannel (with no compression and FULL format) and read it back using Python. Here is the code
exrFile = OpenEXR.InputFile('fallroad_0001.exr')
header = exrFile.header()
dw = header['dataWindow']
pt = Imath.PixelType(Imath.PixelType.FLOAT)
size = (dw.max.x - dw.min.x + 1, dw.max.y - dw.min.y + 1)

cc_r = np.fromstring(exrFile.channel('RenderLayer.Combined.R', pt), dtype=np.float32)
cc_g = np.fromstring(exrFile.channel('RenderLayer.Combined.G', pt), dtype=np.float32)
cc_b = np.fromstring(exrFile.channel('RenderLayer.Combined.B', pt), dtype=np.float32)
cc_r.shape = cc_g.shape = cc_b.shape = (size[1], size[0])
cc = np.dstack((cc_r, cc_g, cc_b))

I understand that an OpenEXR file contain a 'raw' value of the pixel (in high dynamic range), so the pixel values are not in the image standard range [0, 1]. Indeed, here is the range of each channel
[(0.0, 270.6739501953125), (0.0, 221.4493865966797), (0.0, 106.66129302978516)]
Now I am having problems to convert it to the image that Render shows (and export as png), which ranges in [0, 255] or [0, 1]. Scaling [min, max] to [0, 1] or cut off at 1 (values that are greater than 1 become 1) does not work.
I include here the images that I have hand-on. From left to right:  image with raw exported float values, image with value cut-off at 1 (all > 1 become 1) and image rendered by Blender

After hours of endless Googling around, I have figured out an answer for the question. Any other comments would also be welcomed.
The problem is basically because the way Blender store color value interally (and in OpenEXR format) is using linear space, while PNG and other image format is Display Space, or sRGB (ref http://blender-manual-i18n.readthedocs.io/ja/latest/render/post_process/cm_and_exposure.html).
So in other words, my problem is to convert color values from linear space to sRGB, which is discussed at length here https://stackoverflow.com/questions/12524623/what-are-the-practical-differences-when-working-with-colors-in-a-linear-vs-a-no. TL;DR, the formula is
float linear = do_processing();
float s;
if (linear <= 0.0031308) s = linear * 12.92;
else s = 1.055 * pow(linear, 1.0/2.4) - 0.055; ( Edited: The previous version is -0.55 )

With just one small twist, to cut off at 1 any resulted values that higher than 1, and I got the image that I want.

Thanks for your comment, the CDL maybe something that is useful, I'll look into it. Just to make clear, my question was to get back the image that Blender shows when render (and exported as png) since I got a mismatch when exported as png and openexr. Yet, I understand that we've got more than just 1 way to map between linear space and display space.

Both "linear" and "display" are not spaces. To get a perfect 1:1 with the default view transform (which is the sRGB EOTF) simply apply the transform via OpenColorIO's ociolutimage, or via the Python stubs to transform the scene referred values.

The values are scene referred.
You require a view transform to map to the display referred range.
If you choose to use the sub-optimal sRGB EOTF, you are losing a heck of a lot of dynamic range. You can use a much wider dynamic range for the scene referred to display referred transform if you wish. Ultimately it is always a creative decision.
See Render with a wider dynamic range in cycles to produce photorealistic looking images for more information.

Bumped by the same question (the need to easily/automatically convert multi-layer EXR to sRGB PNG images), i wrote another py-script for this task. May be someone find it useful too.
This script automatically exports layers from multi-layered EXR into set of PNG images. With proper Linear->sRGB conversion (and keeping alpha where appropriate) and layer naming. Most of all - it does not use OpenEXR python bindings (it`s a hell to setup them in Windows environment), it just utilizes oiiotool.exe from OpenImageIO suite
https://github.com/IPv6/kristallum/blob/master/blender/scripts/_exr_extractlayers.py

Python version of AugLe's answer:
def norm(val):
    return val * 12.92 if val <= 0.0031308 else 1.055 * val**(1.0/2.4) - 0.055
norm = numpy.vectorize(norm)

def openEXR_RGB_to_mat(path):
    image = OpenEXR.InputFile(path)
    x, y = get_exr_dim(image)
    im = numpy.zeros((x,y,3))

    im[:,:,0] = numpy.frombuffer(image.channel('R'), dtype=numpy.float32).reshape((x,y))
    im[:,:,1] = numpy.frombuffer(image.channel('G'), dtype=numpy.float32).reshape((x,y))
    im[:,:,2] = numpy.frombuffer(image.channel('B'), dtype=numpy.float32).reshape((x,y))

    im = numpy.clip(im, 0, 1)
    return norm(im)


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UV map repeating on mesh when unwrapped
I am unwrapping a mesh of a boot to get ready for texturing but I have never seen this happen before. As you can see with the pants those are using the same texture and have unwrapped fine. The scale and everything is as it should be on the boots but I can not figure out what is going on. Any help would be greatly appreciated.

Hello, maybe show your Shader Editor, and also make sure that you're using the good UV map?

Under "Object Data Properties" and under "UV Maps" I deleted and made a new index and that fixed it.


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How can I edit the number on a property data block?
I have a property to hide a pair of glasses and hair on a character so it is easier to animate, but I want to change the number that turns the glasses off. When the property is 0 the hair disappears but the glasses are on, how can I change the glasses to disappear when the property is set to 0 instead of 1?
Here is a link of the glasses turned on and off- https://i.sstatic.net/dgxeg.jpg

This may help https://blender.stackexchange.com/questions/31962/switching-visible-objects-via-driver/31967#31967

So Python has the keyword [not] and operator [ ! ].  1 - x  == 1 when x  is zero.  Next.  1 - x ==  zero when when x is 1.  This is called invert or inversion.  Python can convert 1 and zero .. to True and False respectively.   So these little facts can be used in a Python Driver.  Driver can be copied and pasted and modified.

Can you state your level of Python familiarity?  Beginner, Intermediate, Experienced, Very Experienced might be some choices.  I understand about 50% of what you wrote.  Perhaps 50% is adequate for a comment.  I suggest a screen capture of your Blender UI, to make your statement a bit clearer.  Lastly many readers, perhaps including you, can create an example like the one listed above and propose an answer. I hope that will happen and you can vote for someone who needs points.

@atomicbezierslinger I have zero experience with python. I'm just an animator/modeler lol

The first example I provided may be enough ... basically you are asking the question .. in Python .. is the value zero or one. If x ==0 or ... if x == 1.  I do not see a screen capture, so some will interpret your question as a little vague.  I hope you will consider an answer from someone with less than 3000 points.

@atomicbezierslinger My bad here is the screenshot https://imgur.com/a/ups6JZ0

The goal is for you to provide the screen shot in your original question so that many readers will see it.  Many readers who need points can answer your question with the comments already provided.  Please place the image in your original question.   I am commenting and trying to accelerate an answer from others.  I am not trying to place an answer in this question.  Many others can do that.  Lastly the system will suggest we limit comments.  Thanks for your time.

Hi Elven, although i am sure you don't wanna read it, but if you want to use not just very basic drivers you should learn at least some basic python. Of course we could now present a perfect answer for you by describing every little detail how to do that. But you wouldn't understand why it is working. So that's just my opinion, but that's a bit "waste of time" in my eyes. And if you are willing to learn a bit python you would be able to do some great things with it and it will open new horizons for you. That's a bit like carrying a baby from one place to another instead of teaching him to run.

@Chris I would be willing to learn some python if it will help me create a better animation workflow for myself. Where would I go to learn some basic python for blender?

@Elven_Randomness: That's depends strong on your likings. If you like learning by videos, e.g. here: https://www.youtube.com/watch?v=rfscVS0vtbw


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Fk to IK on arm is causing arm to rotate
When I change from FK to IK on my character's arm the bicep rotates, what is causing this and how do I fix it? I think it's something to do with the bone locations in the arm but I'm not sure how to fix it if that is the issue.

I think you'll have to share your file, or a stripped-down version of it, to get a definite answer to this one, on https://blend-exchange.com/. Without it, there's too much guesswork.

@RobinBetts I have added the blend file if you are willing to look at it for me.

If you just slide the IK-FK sliders, all you do is switching across modes with.
If you want to keep the pose as is, you need to use these buttons that will snap the current mode's controllers to the other:

That was part of the problem yes, I needed to get the FK>IK and IK>FK to be the same when I switched modes but I needed to apply the pose as rest pose and that fixed my issue.


text:
Mesh doesn't follow the armature after Armature Deform with Automatic Weights
I've been learning blender for a couple of days now and I have a problem that I couldn't solve. I'm following this tutorial btw: https://www.youtube.com/watch?v=XkiWBSSuxLw&ab_channel=Imphenzia. I selected the body and then shift selected the armature then CTRL + P and "Armature Deform with Automatic Weights" as he did in the video, but when I move the armature, the mesh doesn't follow it. It stands still. Here are some screenshots below.

EDIT: https://pasteall.org/blend/019d7eadd4014632a3fd219e67f6f634 -> File

hello, please share your file (upload and share the URL): https://pasteall.org/blend/

added the link to file

Your parentage actually failed. What you need to do is:

Delete all the vertex groups (in the Object Data panel > Vertex Groups list, down arrow button on the right > Delete All Groups)
Some normals are inverted, select your object and in Edit mode, select all and press ShiftN in order to recalculate the normals.
You have overlapping vertices, select your object and in Edit mode, select all and press M > Merge by Distance

Parent again, it should work

it works. Thanks man.


text:
Objects are not emitting light
The 80s sun is not emitting light at all but the pink grid is emitting but not as much as needed even though i put the strength right up.It was emitting fine on the grid but i must have changed something and now not emitting as much. I have got into a mess with this. Thanks. (I've also lost the menu bar in the node editor, it appears again when i render.)
Sun settings

pink grid settings

rendered image

more settings of sun

Why are you plugging the alpha output of the gradient node into the strength socket of the emission node for the sun material? You could simply adjust the value directly without plugging anything into that socket, like you did in the grid material.

I didnt mean to plug it to the material , however when i did it gave it the depth of color i was after by accident. (new to blender still:( With it unplugged it does now emit light but looks a different shade, not sure how to replicate what i had before and have it emit. with alpha not connected it looks like the new image above

thanks i'll try this

Also, you might think about what's there to receive the light, to give cues that it's being emitted? If it's the atmosphere, you might consider Bloom in EEVEE, or volumetrics in Cycles..


text:
How do I render Glowing text effect
My querie probably demos my lack of current understanding of the basics, I'm in the early stages still of getting to grips with Blender, I have a simple animation i'm rendering.
Issue: Trying to render text emitting a glow. In nodes, i added a viewer and emission/glare etc and it shows in the "viewer" -(pictured) exactly as i want but in the box below rendering when rendering f12 it shows no emission from text, not sure what has happened.

The compositor only starts to process the image once the rendering is completed or if you have auto render enabled and already render (a partial) image, once you change the node configuration. You'll have to render the image once from start to finish, to have the entire image processed by the compositor.

Once it's finished you can view the result by switching to Composite instead of Render Layer in the drop down of the image viewer.

many thanks:) I've rendered as you said fully, the bottom viewer is on compositor and still rendered with no light emission showing what is the next step, didn't quite understand. New pic above.

Ah right, you also need to connect the output of the Glare node to the Composite node.

i'm prob doing wrong but tried connecting from "image" on glare node to "image" on the composite node but it made the connection from render layers to composite connection disappear

The compositor only starts to process the image once the rendering is completed or in case you have activate Auto Render once you change the node configuration.
There is a small error in your compositing nodes, in order to see the result in the image editor you have to connect the Image output socket of the Glare node to the Composite node.

Once this adjustment has been made, you can render the image from start to finish. The result of the compositing can be viewed in the image editor if you switch from Render Layer to Composite in the dropdown next to the slots.

Brilliant, thanks:) That worked, have rendered an image with the light emitting, i clicked composite and it swaps between layers, I need to read up on rendering to understand more.I'll learn.  Thanks again.


text:
Create height-map/displacement map for simple object like baseball cap
Is there any way to create height map for some simple objects like baseball cap? (only part of the image is enough -the front printing area of cap shown below)
I want to print/warp some image on some object(cap,mug,...) with displacement map. Kind of custom design for people to upload different images like the below image of 'deer'.
below is what the displacement map will used for. The effect is what I got from some website.
input image

using displacement map to get the result below

may be helpful to explain what I need

An examples of what I need:

I have the user image which need to be distorted

Using software like Photoshop or Python code, I could get the final result of distorted image like below. Similar to Print/Warp something on a 3d object.

Can you also add an example of what type of output you need? Is this for 3d parallax mapping that is currently so popular on social media?

Jackdaw, example added. May be different from 3d parallax mapping, I just need do 2d displacement map. :)

It should be possible to just add an emissive material with the texture coordinates used as color input. You will need to make sure that the color management profile is linear so the data is retained (I think that this can be done by setting the Display Device to None).  I can't try this out without the exact setup of the output.

How to add an emissive material? I am new to 3d software like blender. ..

I suggest that you watch trough the https://www.youtube.com/watch?v=Hgfto0JM_jA&t=2s . It's for 2.79 but should transfer fairly well to 2.8.


text:
Mesh not affected by armature after saving and sharing blend file
I have a .blend file (Blender 2.9 not 2.8) with a model parented under an armature. In my coworker's computer the mesh is properly rigged and animated but when they send me the file the mesh is no longer affected by the armature and its animation.
The mesh is still parented under the armature in the Outline panel and if I reparent it specifying "Armature Deform" and "Automatic Weights" with some minor adjustments to position and rotation it works again.
Any idea on why this is happening and how can we fix it?

If your coworker has 3.0, it's because opening a .blend saved in 3.0 in an older version will lose vertex groups (link).

The mesh gets deformed if:

it has an armature modifier targeting the rig
the mesh has some vertex groups with the same exact name of the bones of the rig, and some vertex weights assignements
the rig is in pose position and not in rest position

The most common problem of breaking the rig is when you import a datablock into a file which has already another datablock with the same name: a .001 suffix is added to the imported one, so the name corrispondence is broken and the rig doesn't work anymore.
To avoid those kind of problems check  in your broken files the names of:

target rig in the armature modifier vs name of the rig
vertex groups of the mesh vs bones of the rig.

During automatic weighting the parentship relation between mesh and rig is added for convenience, but it's not crucial.
It's a good habit, but it's essential when dealing with multiple Rigify rigs into the same file, to generate from metarig using the advanced features that let you assign an unique name to every armature. If not name conflicts like this will arise.
If this doesn't solve, please upload your broken file.

Found the problem. The file was saved in Blender 3.0 while I was trying to load it in Blender 2.9 (correction from original question in which I said 2.8).
After updating blender to 3.0 the issue was fixed


text:
Custom icons for my add-on doesn't work!
I am making custom icons for my Blender add-on. I read the bpy.utils.previews.ImagePreviewCollection already. I tried code and set the __file__ to bpy.context.space_data.text.filepath it works very well.
But, when I add the codes to my add-on file, it doesn't show the icon. Here is the code:

#Add-on info
bl_info = {
    "name": "Shader",
    "author": "me",
    "version": (1, 0),
    "blender": (2, 92, 0),
    "location": "View3D > Toolbar > Shader",
    "description": "Add shaders to your object",
    "category": "3D View",
}

import os
import bpy
from bpy.types import Operator
from bpy.props import StringProperty, IntProperty
from bpy.types import Panel

# Main panel for adding colour to object
class ShaderPanel(bpy.types.Panel):
    bl_label = "Shader"
    bl_idname = "ShaderPanel"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = 'Shader'

    def draw(self, context):
        layout = self.layout
        pcoll = preview_collections["main"]
        row = layout.row()
        my_icon = pcoll["my_icon"]
        your_icon = pcoll["your_icon"]

        row.operator("render.render", icon_value=your_icon.icon_id)
        row.operator("render.render", icon_value=my_icon.icon_id)

classes = [ShaderPanel]

preview_collections = {}

def register():
    from bpy.types import WindowManager
    from bpy.props import (
        StringProperty,
        EnumProperty,
    )

    ############ Custom Icons ############
    import bpy.utils.previews
    pcoll = bpy.utils.previews.new()

    # path to the folder where the icon is
    # the path is calculated relative to this py file inside the addon folder
    my_icons_dir = os.path.join(os.path.dirname(__file__), "icons")

    # load a preview thumbnail of a file and store in the previews collection
    pcoll.load("my_icon", os.path.join(my_icons_dir, "icon.png"), 'IMAGE')
    pcoll.load("your_icon", os.path.join(my_icons_dir, "icon1.png"), 'IMAGE')

    preview_collections["main"] = pcoll
    #######################################

    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():

    for pcoll in preview_collections.values():
        bpy.utils.previews.remove(pcoll)
    preview_collections.clear()

    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    __file__ = bpy.context.space_data.text.filepath
    register()

I did not get error, but it doesn't show icon. Here is what I got:

Here is the folders and files/images location:

Please help me, I already read many common questions but that doesn't solve my problem.

Hello ! While it's nice to provide a working code example, could you restrict it to the part that's responsible for drawing the UI so it's easier to pinpoint it ? Thanks in advance :)

@Gorgious I don't understand what you want me to do. Do you mean there is too many codes on it that uneasy too read?

Do you know why my code doesn't work, but the code in documentation works?

Yes, I'm saying it would take me 10 mins to read through all of your addon code to try and find out what is wrong, while if you isolated the part that's responsible for drawing the UI in the panel, that time would be much faster

@Gorgious Now, I edited. I already put those unrelated codes away and pls see my codes and find what's the problem. thanks

Your path to resources is wrong:
my_icons_dir = os.path.join(os.path.dirname(__file__), "icons")

See template ui_previews_custom_icon.py:

IMPORTANT NOTE: You need to replace the image path with a real existing one.
For distributable scripts, it is recommended to place the icons inside
the addon folder and access it relative to the py script file for
portability

For this we can use bpy.utils.user_resource(resource_type, path='', create=False) link
Script:
#Add-on info
bl_info = {
    "name": "Shader",
    "author": "me",
    "version": (1, 0),
    "blender": (2, 92, 0),
    "location": "View3D > Toolbar > Shader",
    "description": "Add shaders to your object",
    "category": "3D View",
}

import os
import bpy
from bpy.types import Operator
from bpy.props import StringProperty, IntProperty
from bpy.types import Panel

# Main panel for adding colour to object
class SHADER_PT_PANEL(bpy.types.Panel):
    bl_label = "Shader"
    bl_idname = "SHADER_PT_PANEL"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = 'Shader'

    def draw(self, context):
        layout = self.layout
        pcoll = preview_collections["main"]
        row = layout.row()
        my_icon = pcoll["my_icon"]
        your_icon = pcoll["your_icon"]

        row.operator("render.render", icon_value=your_icon.icon_id)
        row.operator("render.render", icon_value=my_icon.icon_id)

classes = [SHADER_PT_PANEL]
preview_collections = {}

def register():
    from bpy.types import WindowManager
    from bpy.props import (
        StringProperty,
        EnumProperty,
    )

    ############ Custom Icons ############
    import bpy.utils.previews
    pcoll = bpy.utils.previews.new()

    # path to the folder where the icon is
    # the path is calculated relative to this py file inside the addon folder
###    my_icons_dir = os.path.join(os.path.dirname(__file__), "icons")

    # this path is for installed addons in user_resources ; doesn´t work as script , for script you need a path to your resources
    my_icons_dir = bpy.utils.user_resource('SCRIPTS', path='addons\Shader' , create=False)   # assuming addon folder is called 'Shader'

    # load a preview thumbnail of a file and store in the previews collection
    pcoll.load("my_icon", os.path.join(my_icons_dir, "icon.png"), 'IMAGE')              # assuming '*.png' is inside folder 'Shader'
    pcoll.load("your_icon", os.path.join(my_icons_dir, "icon1.png"), 'IMAGE')

    preview_collections["main"] = pcoll
    #######################################

    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():

    for pcoll in preview_collections.values():
        bpy.utils.previews.remove(pcoll)
    preview_collections.clear()

    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    __file__ = bpy.context.space_data.text.filepath
    register()

according to your answer, my code should change to my_icons_dir = bpy.utils.user_resource('SCRIPTS', path='Shader Adder\icons' , create=False) since my path is \Documents\Scripting\Blender\Shader Adder\icons but this doesn't work. Please tell me what is the problem, thx

Another question about your answer, you tell me to see template ui_previews_custom_icon.py, but my code is copy from it. You also note that I need to replace the image path with a real existing one, so my code has: __file__ = bpy.context.space_data.text.filepath .

print(bpy.utils.user_resource('SCRIPTS')) returns the folder where installed (!) user addons are saved in a subfolder called addons. For this path='addons\Shader Adder\icons'if addonfolder is Shader Adder and icons in subfolder icons.
bpy.context.space_data.text.filepath is the path from where a file was loaded into the text editor.

Thank you very much for answering. I understand now.


text:
OpenEXR making sense of RGB float values
I rendered and exported a scene with cycles as MultiChannel OpenEXR, then read it back in with OpenEXR binding for Python. The header looks like below. As it indicates, most of the field are floats (32 bits as I've saved with FULL option). I expect them to be in the range of [0, 1] which I can reconstruct to RGB value by multiplying with 255. However, it turns out that the values don't belong to any specific range which is confusing me. For example, the min and max values of each channels of the Composite.Combined are:
[(0.0, 270.6739501953125), (0.0, 221.4493865966797), (0.0, 106.66129302978516)]
So what do these values mean? And is there a way to reconstruct the RGB image that Blender renders? My intention is to simulate the way Blender render with all the passes.
PS: simply normalize these values to the range [0, 255] does not work. Somehow most of the pixels are around 1. or 2., but some get very large.
My code to extract image data is as follows:
exrFile = OpenEXR.InputFile('fallroad_0001.exr')
header = exrFile.header()
dw = header['dataWindow']
pt = Imath.PixelType(Imath.PixelType.FLOAT)
size = (dw.max.x - dw.min.x + 1, dw.max.y - dw.min.y + 1)

cc_r = np.fromstring(exrFile.channel('RenderLayer.Combined.R', pt), dtype=np.float32)
cc_g = np.fromstring(exrFile.channel('RenderLayer.Combined.G', pt), dtype=np.float32)
cc_b = np.fromstring(exrFile.channel('RenderLayer.Combined.B', pt), dtype=np.float32)
cc_r.shape = cc_g.shape = cc_b.shape = (size[1], size[0])
cc = np.dstack((cc_r, cc_g, cc_b))

The header information is as follows
{'BlenderMultiChannel': 'Blender V2.55.1 and newer',
'Camera': 'Camera',
'Date': '2016/10/17 10:23:17',
'File': '/home/FallRoad/FallRoad_render1.blend',
'Frame': '015',
'RenderTime': '11:30.66',
'Scene': 'Scene',
'Time': '00:00:00:15',
'channels': {'Composite.Combined.A': FLOAT (1, 1),
'Composite.Combined.B': FLOAT (1, 1),
'Composite.Combined.G': FLOAT (1, 1),
'Composite.Combined.R': FLOAT (1, 1),
'RenderLayer.Combined.A': FLOAT (1, 1),
'RenderLayer.Combined.B': FLOAT (1, 1),
'RenderLayer.Combined.G': FLOAT (1, 1),
'RenderLayer.Combined.R': FLOAT (1, 1),
'RenderLayer.Depth.Z': FLOAT (1, 1),
'RenderLayer.DiffCol.B': FLOAT (1, 1),
'RenderLayer.DiffCol.G': FLOAT (1, 1),
'RenderLayer.DiffCol.R': FLOAT (1, 1),
'RenderLayer.DiffDir.B': FLOAT (1, 1),
'RenderLayer.DiffDir.G': FLOAT (1, 1),
'RenderLayer.DiffDir.R': FLOAT (1, 1),
'RenderLayer.DiffInd.B': FLOAT (1, 1),
'RenderLayer.DiffInd.G': FLOAT (1, 1),
'RenderLayer.DiffInd.R': FLOAT (1, 1),
'RenderLayer.Emit.B': FLOAT (1, 1),
'RenderLayer.Emit.G': FLOAT (1, 1),
'RenderLayer.Emit.R': FLOAT (1, 1),
'RenderLayer.GlossCol.B': FLOAT (1, 1),
'RenderLayer.GlossCol.G': FLOAT (1, 1),
'RenderLayer.GlossCol.R': FLOAT (1, 1),
'RenderLayer.GlossDir.B': FLOAT (1, 1),
'RenderLayer.GlossDir.G': FLOAT (1, 1),
'RenderLayer.GlossDir.R': FLOAT (1, 1),
'RenderLayer.GlossInd.B': FLOAT (1, 1),
'RenderLayer.GlossInd.G': FLOAT (1, 1),
'RenderLayer.GlossInd.R': FLOAT (1, 1),
'RenderLayer.IndexMA.X': FLOAT (1, 1),
'RenderLayer.IndexOB.X': FLOAT (1, 1),
'RenderLayer.Shadow.B': FLOAT (1, 1),
'RenderLayer.Shadow.G': FLOAT (1, 1),
'RenderLayer.Shadow.R': FLOAT (1, 1),
'RenderLayer.SubsurfaceCol.B': FLOAT (1, 1),
'RenderLayer.SubsurfaceCol.G': FLOAT (1, 1),
'RenderLayer.SubsurfaceCol.R': FLOAT (1, 1),
'RenderLayer.SubsurfaceDir.B': FLOAT (1, 1),
'RenderLayer.SubsurfaceDir.G': FLOAT (1, 1),
'RenderLayer.SubsurfaceDir.R': FLOAT (1, 1),
'RenderLayer.SubsurfaceInd.B': FLOAT (1, 1),
'RenderLayer.SubsurfaceInd.G': FLOAT (1, 1),
'RenderLayer.SubsurfaceInd.R': FLOAT (1, 1),
'RenderLayer.TransCol.B': FLOAT (1, 1),
'RenderLayer.TransCol.G': FLOAT (1, 1),
'RenderLayer.TransCol.R': FLOAT (1, 1),
'RenderLayer.TransDir.B': FLOAT (1, 1),
'RenderLayer.TransDir.G': FLOAT (1, 1),
'RenderLayer.TransDir.R': FLOAT (1, 1),
'RenderLayer.TransInd.B': FLOAT (1, 1),
'RenderLayer.TransInd.G': FLOAT (1, 1),
'RenderLayer.TransInd.R': FLOAT (1, 1),
'RenderLayer.Vector.W': FLOAT (1, 1),
'RenderLayer.Vector.X': FLOAT (1, 1),
'RenderLayer.Vector.Y': FLOAT (1, 1),
'RenderLayer.Vector.Z': FLOAT (1, 1)},
'compression': NO_COMPRESSION,
'dataWindow': (0, 0) - (1919, 1079),
'displayWindow': (0, 0) - (1919, 1079),
'lineOrder': INCREASING_Y,
'pixelAspectRatio': 1.0,
'screenWindowCenter': (0.0, 0.0),
'screenWindowWidth': 1.0}

Edited: I include here the images that I have hand-on. From left to right: the image display with original float value, the image with float cut-off at 1 (all > 1 become 1) and image rendered by Blender

The code and everything was fine, the answer of Leander also gives good general view of the problem and shows how the final image of Blender is constructed. Yet, I think the concrete answer to the original question could be: these values contained in an openexr file is in linear space (high-range) while images exported as png is in display space (sRGB, low-range). To convert from linear-space to sRGB, a simple formula is described here
convert OpenEXR float to color value

I will use nodes rather than code, since they are more visual, hence easier to understand.
I will use the following example scene.

Diffuse Walls (1, 1, 1)
Emission (1, 1, 1) with 0.9 strength
Emission (red / blue) with 32 strength
Cube consiting equally of Diffuse, Glossy, Tranmissive and Scattered shaders (all with different colors)

Rendering and saving the scene as a .exr file will have the main advantage of color correcting all channels individually.
The 32 bit float values ensure, that even extremely dark values will have proper colors and show no banding when multiplying with numbers larger than 1.
Some areas of the image appear very bright. They have RGB values above (1, 1, 1). Higher values can only be displayed as (1, 1, 1), since monitors can't get brighter than white. These areas will still display the correct colors after multiplying them with numbers smaller than one.
A pixel with numbers larger than 1 like (4, 1, 1) will be display as (1, 1, 1) [white]. But after doing a color operation like dividing by half the floating bit pixel will still have the correct relative color (2, 0.5, 0.5) [red]. If the pixel would have been clamped to (1, 1, 1), the operation would produce a gray pixels (0.5, 0.5, 0.5).
The RGB channels should be mapped correct already. (0, 0, 0) producing black and (1, 1, 1) producing white. All lower values than 0 will show as black, all higher values than 1 will show as white.
An .exr can contain more RGB information than monitors can display.

Mapping Blenders output channels.
The beauty pass (combined) is made up from:
EmitDiffDir, DiffInd, DiffColGlossDir, GlossInd, GlossColTransDir, TransInd, TransColSubsurfaceDir, SubsurfaceInd, SubsurfaceCol
All other channels have additional information (e.g. shadow), which is not used/needed to construct the rendered image.
For each of the pass types (Diffuse, Glossy, Transmission, Subsurface), the procedure will be to add the Direct and the Indirect, then multiply them with the Color. Direct and Indirect passes are unpremultiplied, Color passes are premultiplied. Hence the product of the three will be premultiplied.
(Dir + Ind) * Col

The resulting five light pass types are Emission, Diffuse, Glossy, Transmission, Subsurface. Since the example cubes shader has different colors for each pass type, we can easily identify then.

Each pass type will add to the final image.
Emit + [(DiffDir + DiffInd) * DiffCol]
  + [(GlossDir + GlossInd) * GlossCol]
  + [(TransDir + TransInd) * TransCol]
  + [(SubsurfaceDir + SubsurfaceInd) * SubsurfaceCol]

The exr can be loaded into the compositor and the passes combined as explained. The final Add node holds the same information as the Combined pass.

to confirm, the formula to derive the final image is done on plain float values, i.e. the results could be stacked up to very high values? In that case, how can I get the RBG values that Blender uses in its final images? What is the good way to scale down the high-range value to the normal monitor-friendly values since the usual min-max to 0-1 wouldn't work?

After adding the channels together, no scaling needs to be done. You can simply ignore all higher values. If values higher than 1 cause a problem, you can clamp them to one. It should not look any different

I've edited my question with sample images following your idea, but it look better now but still so dark. Any idea why?

Here's one thing that I missed, that is the color display in Blender's render or png image is in sRGB space (generally display space), which is  low-range, while the openexr (and what Blender stores internally) is in linear space (much higher range). So just simply flooring down everything higher than 1 back to 1 wouldn't work. I found an answer for my problem, here

Use a proper view transform. This overcomplicates and muddles up the simplicity of a proper view transform. OpenColorIO's ociolutimage works fine for this in post, and can perfectly apply view transforms that you see live in the viewport.

Bumped by the same question (the need to easily/automatically convert multi-layer EXR to sRGB PNG images), i wrote another py-script for this task. Why? OpenEXR python bindings are really hard to setup in Windows environment. I tried a lot. So may be someone find this solution useful too.
This script automatically exports layers from multi-layered EXR into set of PNG images. With proper Linear->sRGB conversion (and keeping alpha where appropriate) and layer naming. It does not use OpenEXR python bindings, it just utilizes oiiotool.exe from OpenImageIO suite
https://github.com/IPv6/kristallum/blob/master/blender/scripts/_exr_extractlayers.py

wow, it sounds like a very useful tool. yet, I'm wondering if the similar thing can be done on linux? I have to use Python's OpenEXR package, and to install it is somehow a nightmare to me when moving to a new machine

Yes, the same script can used everywhere where oiiotool can be run, so on linux too.
I am using it on Windows and MacOs, the only change - path to oiiotool inside script


text:
Importing 16:9 into 2:1 while maintaining the original aspect ratio
I am importing a 16:9 video (1920x1080) into a 2:1 edit (2048x1024) and every time I do, the imported video's aspect ratio changes a little making it look stretched. I can correct by adjusting the scale, but then that seems create blocking artifacts in the final render no matter what bitrate I use. Is there a way to import and keep the 16:9 ratio without having to adjust the scale?
Background.  In my case I am using Blender to render Virtual Reality video.  Been using it successfully for over a year with great results. I simply import the left and right eyes into blender (which are two perfectly round fisheye videos) edit and render. I capture content in 16:9 video but in order to use a new VR streaming tool, I need a 2:1 aspect ratio.
Much appreciated.
Source

Output

Have you tried texturing a plane with the 16:9 video and "filming" that from a camera, setting your output dimensions to the 2:1 ratio?  Use the "Generated" mapping option to see how that goes first.  Scale the plane's X/Y axis separately.  You might avoid the artifacts that way.   I've made quite dramatic changes to imported videos using this method and so far without hassles.

I added a sample output video (side by side fisheye) and a sample input (single fisheye). The output is 2048x1024 and the input is 1920x1080.  @Edgel3D That sounds very complicated. I have been scaling the X/Y axis separately and while it looks good in Blender, the final render has blocking artifacts.

https://www.youtube.com/watch?v=LX_c8tmUnOg&list=PLjyuVPBuorqIhlqZtoIvnAVQ3x18sNev4&index=7

In the VSE under Strip Input you can enable image offset - this keeps the original resolution and allows you to position the strip within the final video.

Filming off a 2D plane is far simpler than using the VSE with effects strips etc.  Scaling can be tested with the convenience of WYSIWYG when you render using "OpenGL".  It's a lot faster too.
If it turns out you cannot solve this and haven't tried or unable to set my suggestion up, leave a comment here and I'll make a Blender file up for you to use.  There's very little involved.


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Normal maps not working in blender internal in 2.78 update
I was just wondering because ever since blender 2.78 normal map data would not be displayed in the final render. However it is displayed in GLSL (viewport). Below is an example of said problem.

Am I missing a new feature or is this a bug? If this is a bug has anyone else encountered this problem and is it being fixed? I would very much like to use the new features in 2.78 but this problem is really annoying me.
edit: If I check tangent shading the normal data is used. This is strange. Not a  fix but. ..

In the Image settings (visible in your screen shots), try changing the Color Space from sRGB to Non-Color Data. Does this fix it?

Thanks, for the reply, I have played around with the color space as well as the image space (i.e. tangent, world...) I have also tried a node setup with the new normal map node with the gamma correction... pretty much from what I can tell normals just won't work in blender internal.

Oh, my understanding is that you should either use gamma correction or set to Non-Color Data, but not do both. Can you upload the .blend using Blend Exchange?

@Mentalist I have been using blender for 6 years now, this is the first major problem that I have encountered that there was no documentation for (which is why I am asking in many forums). I cannot find anyone however with similar problems in 2.78. I have been scouring the bug lists  with little avail, I think it might be a system error rather than a bug in blender if no one else is experiencing this.

Ok so I was able to 'fix' this problem. For some reason now in 2.78 your mesh requires a uvmap regardless of whether or not it is using said uvmap (global... genereated .etc.) for normals to work as intended. diffuse spec all work fine without it. So to fix this problem with the normal map not working, all that had to be done was just create a uvmap. Weird but... there you have it.

Good to know! Thanks for sharing the solution.

Thank you have been going crazy on this for an hour now!


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How to remove object from collection only?
Using bpy, how do I remove an object from a collection without also removing it from other places?
I have an object that is both part of a collection and at the same time a child of another object. I try to unlink it from the collection:
collection.objects.unlink(obj)

But it also disappears from the other object.
Even in the GUI I can't seem to remove it from only one place in the outliner. How do I do this right?
EDIT:
The reason why I got here:
I have this structure:
 - Collection1
 -   Collection2
 -     Object1
 -       ObjectToBeMoved
 -   Object3

I want to move Object2 from Object1 to Object3. So I do:
ObjectToBeMoved.parent = Object3

I end up with this:
 - Collection1
 -   Collection2
 -     ObjectToBeMoved
 -     Object1
 -   Object3
 -     ObjectToBeMoved

It gets the new parent (Object3) but it also moves up in the hierarchy to become sibling with its former parent, under Collection2. That's why I want to delete it from Collection2. But when I do that it also disappears from Object3.
Is there another, better, way to move an object?

have you explicitly linked ObjectToBeMoved to Collection1 somewhere? I can't see that step in your description. Keep in mind that parenting does not move the object to the other collection, it only sets the parent.

No, they are not explicitly linked. But I suppose that when I change the parent for ObjectToBeMoved, it is no longer a child of Object1, so it somehow "floats up" to the nearest collection.  So if I also make it belong to Collection1 it would disappear from Collection2(?). Can be worth to try at least.

When you unlink an object that is only linked to 1 collection it will become "orphaned", it will still exist in your data but will not be referenced by anything.
You need to link it against at least 1 collection to make it accessible in your Scene.
bpy.data.collections['Defaults'].objects.unlink(bpy.data.objects['Cube.001'])
will remove the object from the collection and make it an orphan which you can see in the "Unused Data" tab.

bpy.data.collections['New_Coll'].objects.link(bpy.data.objects['Cube.001'])
will once again link it to another collection.
I wrote a small operator to help me move objects between collections for this exact reason. It's part of a much bigger addon but you can link it to a button in the "n" menu easily.
from bpy.types import Operator

class CAD_VIEW_OT_move_to_coll(Operator):
    bl_idname = "cad_view.move_to_coll"
    bl_label = "Move Objects to Collection"
    bl_description = "Moves the selected objects to the active objects collection"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"

    @classmethod
    def poll(cls, context):
        return context.area.type == "VIEW_3D" and len(context.selected_objects) > 0

    def invoke(self, context, event):
        active_object = context.active_object
        coll_target = active_object.users_collection[0]
        selected_objects = [obj for obj in context.selected_objects]

        for obj in selected_objects:
            if obj is not active_object:
                for coll in obj.users_collection:
                    coll.objects.unlink(obj)
                coll_target.objects.link(obj)

        return {"FINISHED"}


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Pasted the same uv coords onto multiple faces, but some of them are fliped
So, im trying to paste the same uv coordinates onto multiple faces so they tile nicely,
but every time i do it some of them end up in the wrong direction.
Can anyone please explain why this happens?
I've tried everything, but the only solution i found is to flip every wrong face manually,
but it takes ages.

Are the "flips" completely random, or does it apply to each and every tile and is "flipped" by a constant amount?

Yeah, the direction each face flips the uv is consistent every time, like, even if i paste the coords again, the pattern stays the same.

That's good to know that the flipping is consistent. In that case, you can simply add a Mapping node between the Texture Coordinate Node and whatever's on the other side. Now, just screw around with the Rotation until it corrects the flipping

In Edit Mode, press U then click on Reset.

In the UV Editor, scale all the reset UV's to the correct place on the image.

Thank you but, the thing is, the pattern stays the same even if i reset the uv on every face.

Can you explain what you have done so far to get to where you are? Or if you don't mind sharing, can you upload your blend file after packing external data (File>External Data>Pack External Data) to https://blend-exchange.com/

Sure thing, i didn't know you could post blend files.

I have no idea why it's doing that but un-Subdividing and Subdividing fixes it.


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Render quality is very low
So im trying to render my 11s scene using eeve in blender
-Actual Quality below-

but when I start to render in png sequence using eeve,the quality looks like,

are there any settings that needs to be adjusted im missing ?pls help
camera settings

render settings

can you show us your render and camera settings? OR even share your file? At first it looks like problem that is cause by clip start and end of camera, or maybe it is shadows setting

@MikoCG I added them

Okay, how big is your scene in m*m? You are using clip end 9500 and clip start 0.1, is it needed? Try to set it to 0.1 and 1000 and say if something changed... also 512px and 1024px shadows may cause shadow appearing as little cubes, try to set it to at least 2048 and 2048 or even 4096 (this will make renders longer)

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.


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Geometry Nodes - Align Monkey head to random placed Bodies
How to get rotation of instances?
I want to place monkey head on bodies with proper alignment

Basically, you can just use the position of your instances as the position, but I'm guessing you'll want to put the head on the shoulder as well. Further, I suspect that the instances are different, which should change this position as well. So it all kind of depends on your construction. Maybe it would be good if you share your blend file with us, so we can better understand how you built this: https://blend-exchange.com/

@quellenform, file was attached

You don't really need Geometry Nodes here (even if I think in principle that you can almost always use them).
Here you could work with constraints.
Add the constraint Copy Location and Copy Rotation to the heads, and use the respective body as Target.

But if you really want to use geometry nodes, here's how you can solve it:

Here I simply instantiate the heads at a line (which consists of exactly one point, and is created at the local zero point).
Before that I use the node Transform, so that the head remains a little positionable.
The head automatically inherits the rotation from the rotation of the body.

Update:
You mentioned in your comment: "...and just imagine, that we have thousands of these bodies".
...is 8K enough? or should it be 2M? ...I think it depends on your machine.
Here is a solution where any number of bodies can be combined with any number of heads:

First, here I instantiate the bodies from a collection. Of course you can also use a single object. The bodies and heads themselves have no further modifiers or constraints attached in this setup.
Next, I take the instances, and convert them back to points for instantiating the heads.
this way you can cascade or change it as you need.

Thanx for the answer! Yeah, second method with copying geometry node modifiers to all bodies objects is pretty logical, but what if I want to achieve it with Collection Info Node, without copying geometry node modifier to all body instances
...and just imagine, that we have thousands of these bodies
so we can't just add constraints to all of them and easily tweak

i'm starting thinking, that copying geometry nodes modifier is the only option and the only supported and desired logic by developers, but sadly it's not that handy, that how i want it to be... i mean, to rule all of them from one place

Give me a few minutes, I'll take another look. If I understand you correctly, you want to randomly combine and distribute the bodies and heads from a collection, right?

no, it's not about randomness, i just want to place the head to all bodies in the collection with proper alignment

@AlexanderBicukow ...updated the answer, I hope it helps.

oh, no no, man, i really appreciate your attention to my quastion, but you get it wrong ;~;
by "thouthands bodies" i mean already places instances in scene.
So the task is: you already have many instances places in the model with their rotations, and you need to place monkey head to all of them with propper alignment
I will accept your answer as solved, because i think there is olny one way to do it: copying modifier to all instances by your hands. Thanx again!

@AlexanderBicukow OK, you are right: Geometry Nodes can of course only work if they are added as modifiers. But you could use Python to copy the modifiers to other objects, then you would save yourself the manual copying. That would be an interesting further question (if it hasn't already been answered here).


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Geometry nodes - Rotation to Direction
Why method on picture nor working as intended? It provides some random direction (I want Z direction of object). I just want to copy rotation from object to generated mesh/curve line

Although they are both ordered collections of 3 numbers, Directions and Rotations are different things.

A Direction is a vector in a 3D space, composed of lengths in the X direction,Y direction, and Z direction of that space.
An Euler Rotation is a transformation: a series of angles through which some collection of vectors is rotated about the X,Y, and Z axes of the given space.
In a GN tree, the overall 'space' is that of the modified object; measured along the object's own X,Y and Z axes.

You have plugged a Rotation into a Direction.
The simplest way to line your laser beam up with the your handle would be to make the GN-created beam a modification of the handle, with the handle as the input Geometry. Then, from your illustration, the curve's direction would always be (0,0,-1).
However, if you want the beam to be a modification of another (perhaps dummy) object, then you have to compensate for the difference in orientations between the modified object and the handle.
You want the Direction of the beam to be whatever (0,0,-1) becomes when it has been rotated though the same angles as the handle, so this is one way to get hold of that:

I've glossed over what X,Y and Z are in Euler rotations.. how the rotation about one axis changes the meaning of the rotation about the next, and why the order of rotations matters. This is a nice explanation.

Thank you for your attention!
So there is 3 types of vector data: Coordinate, Euler Rotations and Directions?

@AlexanderBicukow   Strictly, I suppose... 'Coordinates' are just a way of referring to a set of numbers defining a measurement in some space.. (that could be 2D, 3D, Polar, Spherical) ... A 'Vector' is a line with a length and a direction. The difference between one end and the other of a vector is given by a set of coordinates. 'Direction' is the direction of a vector, ignoring its length. Specifically, the vector's length is ignored by setting it to 1: 'Normalizing' it. A 'Point' is where one end of a vector is, when the other end is at (0,0,0).

@AlexanderBicukow  An 'Euler Rotation' is not a vector. But it is an ordered set of 3 numbers, so it can be handled by nodes which expect vectors.


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Geometry nodes - Geometry disappear after Set Position Node
I want to project generated plane (Grid Node) to mine reflection plane with Raycast Node
but geometry disappear after Set Position Node.
Also noticed, that Raycast's "Hit normal" socket is Diamond with Dot
(which is currently a single value for some reason)
.blend File

please provide blend file, thanks.

@Chris , thanx for your attention! Added blend file to the post

UPDATE:
just unplug the source position from your raycast node in your uploaded file.
Then it works.
result:

your basic setup was ok. Looks like you made something wrong with your rotation/positioning calculation.
check out this "simple" setup:

this works. Then i would carefully add an empty just test with translation, if that works, try rotation and so on.
here is the blend file with the simplified setup, but it works ;)

result:

ohhh, the main reason of the problem was the Join Geometry node.
For some reason only after it the geometry shows up. Strange behaviour for me


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Geometry nodes - Float Curve with values greater then 0..1
I'm want to cull points by distance with Hit Distance parameter on Raycast node. Everything is okay, but i want to integrate Curves widget to manipulate gradient dencity more accurate
Camera Culling with Distance Culling.blend

Something like this, but with curve widget and smooth transition

Figured that out. (Sort of..) (Sorry that I can't describe my own question clearly)
So, Curve Floats works with 0..1 float values by default, yes - you can tweak clipping parameter, but that would not be that handy
So it's better to convert your values (for example 0..100) to 0..1 with map range:

I used it twice: to convert to 0..1 and then turn it back, but you need to know the Max value
So now i have more precise control for my gradient ^-^ :

I am not sure how you want it, but this works for me:

or RGB curve:

Thank you! Sadly Curve manipulating has strange behavior for my task
I want to have gradient of point relatively to my camera (for performance)


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Geometry Nodes - Transfer tangent from curve to mesh (curve is a UV seam of mesh twig)
I want to transfer tangent from curve (which is basicly seam of twig)
but transfer attribute produce zeros for some reason
The main problem is that Attribute transfer produces zeros, but Attrubute capture is working fine
Transfer Tangent.blend

There are a few reasons this isn't working..

Capture Attribute captures a field of values on one state of the incoming  Geometry, and 'passes it on' down the green pipe: i.e. down the same Geometry branch. The output Geometry of your capture goes nowhere.. The attributes evaporate.
The 'Target' ( personally, I wish it was called 'Source') of a Transfer Attribute node is the Geometry on which the attribute resides, ready to be transferred from one branch to another, in a manner similar to a Data Transfer modifier. Your 'Target' is the incoming mesh before a selection of it is  converted to a curve. It doesn't have the attributes you want to transfer.
Transfer Attribute can't transfer from a curve (which is a formula for generating points).. only from a mesh or point-cloud, the locations of whose points are nailed down. A Conversion to Mesh will do, generating  points at which the curve is sampled. In this case, those are the original vertices, used to generate the curve in the first place.

Above, the Normal of the curve is sampled as well as the Tangent, in case you want a full orientation of the instances. If you want only the Tangent, the Normal is optional.

An Euler 'Rotation' is a set of three angles. The Tangent and Normal are 3-vectors.. sets of three lengths. To use a vector as a guide to rotation, you can use the utility Align Euler to Vector.

Here, it's used twice. Once to align instance Y the Tangent, and then to spin around the (now set) Y, to align the instance Z to the curve's Normal.

I hope this is the sort of result you are looking for:

That doesn't look right.

@TheJeran remember..  the green arrows point down the tangent pf a poly-curve linearly interpolated,, as sampled a their bases? It looks OK to me .. maybe it would have been better to convert the curve to Bezier, and smooth it, before sampling? Also the sample is coming via 'Nearest', sometimes from the other side of the twig.

@TheJeran   Personally, I would want to generate  the twig from the curve  I sampled the direction from, rather than extract the direction-curve from an existing mesh? But this way is a nice idea,,


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Geometry nodes - Curve to Mesh Brakes UV of Entire Node Group Geometry
when Im using "Curve to Mesh" node, it brakes uv on entire model, even mesh that i'm not modifying in geometry nodes (i just joined it with "Join Geometry" node)

if you are on blender 3.2 or 3.3, there's a known high priority bug with Curve to Mesh can you try this workaround here https://blender.stackexchange.com/a/269904/142292

on another note, i tried your file on blender 3.0, 3.1, & 3.2 and it works fine.

Yes, this a known issue.
https://developer.blender.org/T99915
For now, you can use two ways to bypass this issue:

Use "Geometry to instance" node
Use "UV map node" and define specific UV map


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Geometry nodes - Split Curve by Control Points
I want to split curve by "control points".

I also want to remind, that original's curves points is "Control Points"
You can see it in this node group:

To solve this task you would have to proceed as follows:

Here I first capture the index of each point with Capture Attribute.
Then I convert the curve into a poly curve, which of course removes the Curve Handles.
But this way I can convert the curve into a mesh, which can be split exactly at the original points with Split Edges.
This mesh is transformed back into a curve.
Then you have to convert it to a Bezier Curve again and define the type of the Curve Handles.
Thus you have several curve segments, which were divided at the original points.
So that the curve segments also receive the original form again, you simply transfer the positions of the handles from the original curve to the points of the new segments.

Yeah, this is pretty smart! But can it be solve using "selection" socket in the "split edges" node? Maybe we can transfer some attribute with "Transfer Attribute" node with "near" function..  just for learning

@AlexanderBicukow Split Edges only works with a mesh. But to get the mesh, you have to apply Curve to Mesh before. But this will also resample the curve, which will also give you the extra points. So this is not an option, unfortunately, which is why I also do a multiple conversion here.


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What this artifact is due to?
My solidify modifier thickness is very less. However, I am pretty confident this to be a modeling issue but cannot figure out the problem. White is the intended outline (rim light kind of) but that green thick highlight not what I want.

Here is the part file link. Thank you :) https://blend-exchange.giantcowfilms.com/b/8nJZnesg

Hello, please add a screenshot of your scene, with every object. Might be something else from the scene reflecting from the surface of the bottle, or it might be light refracting inside the material of the bottle

Ok. Let me add them too. I have added blend file link also

You have a spotlight directly behind the bottle, if you disable it or turn down its power does it fix the green bands ?

Yes. It does. But then it removes the white highlight also.

Ok. So the reason was unnecessary solidify modifier I used. Removing it helped and after it was all about adjusting light coming through the bottle.


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Cycles Rendering vs Eevee Reflections difference!

Can anyone tell me why there is extra shading popping up in cycles that is not appearing in EEvee? nothing is changed in both. Everything is the same.
https://blend-exchange.giantcowfilms.com/b/3GYGVzyb

hello, probably because Cycles is correctly reflecting the environment (here, probably your plane) while Eevee doesn't, Eevee reflects lights but not environment unless you use Light Probe. If you share your file we will be able to check

Read my answer here, I hope it will help: https://blender.stackexchange.com/questions/190642/how-do-i-get-proper-reflections-eevee

@moonboots https://blend-exchange.giantcowfilms.com/b/3GYGVzyb here is the link. sure, let me go through your answer too. thank you!

You were right :D that was reflection due to my plane!


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Cannot bevel above certain dimension
I cannot bevel above certain point. I have done merge by distance, remove clamping in bevel modifier. Not sure what is the problem now. There is weird artifacts appearing too.
This is how my mesh looks like

Hello :). There could be many reasons. Consider sharing your file.

Have you applied the scale in Object mode?

@JachymMichal file is added. thank you!

@moonboots yes I have applied the scale too.

it looks like you didn't, it fixes the problem

@moonboots .... Ohhh! too bad from my side. I might have selected back body while checking the object props. Sorry for the trouble.

Apply your scale in Object mode, otherwise your bevel will be distorted. Also make sure that the Amount value is low as your object is rather small:

yes. this resolved my issue! Thank you so much :)


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Eevee render output is black. But it appears in cycles. What I did incorrectly during adjustment?
Till half way of my process, all was good. I was able to produce images but now all I get is black images. Checked world environment and lightings too. No luck. Can anyone please tell me what's wrong?
File size: 21.1mb
Link: https://blend-exchange.com/b/kjKW8Pwn
What setting I messed up?

Could you clarify a few things: what do you mean by half way of your process, you mean that eventually you made some changes which caused the issue? Do you remember what kind of changes you made, to the topology, lightning, output settings, etc. Also what do you mean by black images - I initially thought you mean you get entirely black images, but when I render your project, I get this: https://i.imgur.com/z451M3v.png - if you get the same result, I find "nothing else" in the title misleading. Perhaps a better title would be e.g. "only half of my character renders and it's very dark"

@MarkusvonBroady Yes. It was appearing but I am not sure what changes I did (because I did many) and image appeared black after rendering. Yes, I do entirely get black image. In the link you shared, I don't see anything. It is plain black.

Having a bright, high contrast monitor and good vision, I'm able to see this picture is not completely black:

In future, you can try cranking up the Exposure in Render Properties tab  -> Color Management section (or use compositor to increase contrast etc.) to see what's happening better:

As you can see, your character is cut in half. This happens because the character is overlapped by an object, which also blocks light, putting everything left in a deep shadow.
Right away when you open the uploaded project, you can see the problematic object on the bottom workspace region:

It's not problematic in viewport preview, because it was set to only display as a bounding box in the viewport:

The solution you probably want is to disable rendering of this object by clicking on a camera icon next to the object's name in the Outliner:

Then the render becomes this:

And the reason it worked for Cycles is Cycles-specific properties of the object: all Ray visibility options disabled in the Object Properties tab.

Thank you so so much for this :) It solved my problem.


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I downloaded the latest 3.0 alpha release. I cannot find ambient occlusion under world environment for cycles. Where it is?
In the previous versions, it was under the world tab. I downloaded latest release and now I cannot find it. This is the option I am looking for

This is from the latest release

do you mean the node ambient occlusion? if yes, just tap "shift-a" in the world shader nodes and search for it. It is there.

Wasn't it available as an option in previous versions? I am adding another image in question

yes, you are right. Looks like they deleted or removed the UI element.

Ambient Occlusion settings have been moved to Render Properties > Light Paths > Fast GI Approximation

And that's a good change IMHO. Good to note that Cycles doesn't "need" AO as raytracing does naturally all what AO is supposed to mimic. Technically, we "have AO" without the need of an additional AO effect. So it should be used either for stylized rendering, or very finely dosed.


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Best way to create Godzilla's Atomic Breath (Cycles)?
I've been trying to find tutorials out there that at least have a similar result to what I'm looking for, but I've failed to find anything close enough. I have some experience with particles and cycles, but not enough to find a way to do this on my own. I'm trying to replicate this specific variant.

What would be the best way to recreate this? Any help would be greatly appreciated.
*UPDATE- I managed to make this using volumetric scattering and emission. It's close to what I'm looking for, but I need to make it flow in a specific direction, similar to what is shown in the video I linked. I've attempted using particles and smoke (smoke was a massive headache for me), but haven't gotten any successful results. This is for a film project I plan on working in the future, and is going to be used as VFX rather than a still image.

*FINAL UPDATE- I've finally found a result that satisfied me. I abandoned the 2001 style atomic breath and went with the 2002-2004 breath. What I did was create a cylinder, make it have a short shape key, and a long shape key, and use quick smoke. I make the cylinder share a material with the smoke domain to make it "invisible" in the render (could create a new material but I was just lazy.) I used the fire sim, and In the node editor, set the flame emission like so.

Almost done. To make the the breath flow, I created a wind force, running prefectly along with the cylinder, and parented it to it. Adjust the strength to your desire. Finally, I set the flame to dissolve over time. The dissolve time depends on the length of the cylinder, so there's no set number. There is likely a much better for the flowing movement, but I am still very new to blender, and it works for now. Thank you for the tips and suggestions, I will centainly use them for future work. Here's the final result.

See if these help http://blender.stackexchange.com/questions/53032/how-do-you-use-blender-to-make-pokemon-attacks-like-hyper-beam-and-solar-beam

Those are great tutorials, but not so much the result I'm looking for. I appreciate the suggestions though, thank you.

@MrGodzilla445 You should post your solution as an answer, it's fantastic!

One of the method may be using some Blur (Fast Gausian) nodes in the compositor.

First check the Transparent checkbox in the Film panel of the Render header.

Add a cylinder, subdivide and shape it. Give it the Emission shader. Render image (F12). Go to compositor and add some Blur (Fast Gaussian) nodes with the different bluring values. Use Alpha Over nodes to mix them. Use Color node to color the beam as you like (in my case I used it to color the glow blue).
Use Render Layers (How to render a very complex scene using Render Layers?) to add a background or your scene with Godzilla in it to the final render.

EDIT: You can add two cylinders and place them in two different render layers. Each cylinder may have its own deforming shapekeys to affect the beam transformations. You may then parent both cylinders to the deforming bones. Here's the animated result. I know it isn't exactly the same as in the movie you provided but I guess it's a good start for experiments.

Thank you. It's a great start, but I should have clarified it in the OP, It's not for a still. It's for a film I'll be working on, and I need it to be a physical presence in the world. I'd do the actual breath in after effects, but it tends to look less tangible than something rendered in world.

Please check out my edit. It may be animated. I've uploaded the test animated gif. Using the proper techniqes (Vawe Modifier maybe) it may look the same as in the movie clip you provided.

I think, it would look much better with so me randomnes in the emmision. You could use cloud texture as factor or something like that.

Sorry for replying so late. For a couple days now, Chrome has refused to load Stack Exchange, but It's working now. In that time, I did however find a satisfactory result. I'll still use the tips you gave for future work though. Thank you for your help.

@MrGodzilla445 If you found the proper solution, could you share it with us and post your own answer explaining how to do it? It'll be helpful for the people looking for it in the future.

@PaulGonet Added the steps in the OP.


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Area too thick with Subdiv
I'm working on a dragon, building the base in Blender, and adding the details and textures with Mudbox. One issue I'm having though is the "hands" are is much larger and than it should be with the subdiv applied.

Is there any way I can fix this without applying the modifier and editing it by hand?
Edit:
Wireframe images

Hello. Would you send an wireframe picture?

Sure thing. Added to the OP.

In Edit mode, you can use the cut tool (K) with cut through (Z) to add a small loop around the center of the hand, like this :

After adding the loop, the center of the hand is no longer large (on the bottom, the hand with the loop cut and on the top a mirrored hand without a loop cut :

Thanks mate. Didn't realize it would've been so simple.


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Can the 3D viewport display animated, textured material alpha)?
Is there a way to make the viewport reflect an animated alpha of a texture (not material)?

I create a texture with Z-transaprency and Alpha set to 0.
I create a png texture that has transaprent parts and apply it.
I then animate the texture influence on "Color" and "Alpha".
Everything renders fine viewport - but only when I change values.

Scrubbing the timeline does not display the fade-out animation, which renders fine in the final output.

Possible duplicate of How do I make a transparent material display in the 3D view?

Possible duplicate of Material Opacity in viewport?

Unfortunately neither is a duplicate. My problem is the animated display of a transparent texture. I'm doing motion graphics and try to see a fade-out in the 3D viewport.

As far as I know Blender has limited to no support at all for animated textures in the viewport. GLSL/Blender Internal textures can be animated only for 'offline' output In the viewport they are optimized for speed and hence loose any aut-updating capabilities

I use OpenGL constantly unless Forced to do otherwise.  I've also used it to fade out alpha layered texture pretty much as per your question, albeit with a 'mirror' or two.  You may have already done this, but others may find this useful.

The method is always to animate everything in the 3D window but place the textured model to be faded out in it's own layer.  This allows precise placement/scaling etc.  Objects that will conceal the fading object when it moves behind can be either duplicated in the extra layer, or masks setup to conceal it.
The cloud in this case is our fading object.
Once set up and animating properly, switch off the extra (cloud) layer and render the rest.
We render the cloud's layer next, only output that to alpha layered PNG files, and INTO A SEPERATE FOLDER!  Ensure you are indeed rendering with an alpha layer. (transparency)  At near top left of the 3D window is the "Render" drop-down.  "Render OpenGL image" most often gives you what's going to end up on the video.
Reset your output to it's final rendering folder, file type etc, and ensure the "Post output " is set to "Sequencer".
Go to the Video Editor and bring in the main video render onto the lower strip, the Alpha layered PNG files (as an image) onto one above it, and set the upper strip to "Alpha Over"
All that remains is to set keyframes on the upper strip to fade it in and out at the appropriate frame numbers.
Render that.  All of the renders only takes seconds, including the final one which of course must be from Blender's internal Renderer.
Hope this solves your problem...
PS:  It's also possible to mix the PNG video strip with a "Scene" strip and get the same result.  Unfortunately that has given me some grief in the past so I prefer to use two video strips.

Thanks for your answer, but it looks like you don't actually solve the problem. You seem to be applying the transparency manually via rendered animations. I want the viewport to do the "work" for me, since I rely on getting feedback on animating things directly.

That's an odd one Mr Zak.  To date I've not had any problems storing alpha animations in PNG format.  I simply zip them to a single file if I want to use them again, or re-render them from the archived Blender file. - interesting to read your comment.


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Geometry Nodes: Material's Total Area (Accumulate Field Total Unique)
I want to get area spreadsheet of all materials on mesh, and since there is no domain "materials", i think the best method is place points at mean location of separated by materials mesh, First I thought about set position on mean location of separated by material's mesh and merge it, but i think it's pretty unoptimized method

Geometry Nodes:

Here it stores in faces the added area of faces of the same material. The average position is done by the same way, but the sum is divided by the total of faces with the same material.

You can generate points containing the area and material index for each material doing this:

Edit: accurate center position (based on vertex position)

With this method, for every material, you will need to add new row of nodes, set the material index and add a switch to get the value when the point index is equal to the material index selected.

You will also need increase the point count to the new material count.

So, this is pretty good example for understanding the Accumulate filed node i guess


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Geometry nodes - How to Knife project procedurally
Is it possibple to knife project in geometry nodes procedurally? Like knife project tool

Expanding on @Bicukow's answer just a bit, I added a part to allow you to rotate and aim the cutter object as you like. I also think this way is a bit cleaner for getting the intersection with more complex geo, the one-mesh boolean method caused some weird triangulation. It did however subvert the interior face issue so... shrugs

Either way it's a bit fiddly but it works.

Geometry node setup is pretty funky, but its working through boolean node (difference), but you actually need to join both mesh and extruded curve before using and leave second slot of boolean node empty, then just delete faces of extruded mesh using attribute capture node before boolean. ¯_(ツ)_/¯
Note: This is the stablest way to knife project, but on complex geometry it will triangulate faces, that will be cutted.