Blender Light Streaks TUTORIAL

Make a real time light streak effect in Blender using Eevee render engine set to just 1 sample.

[@IanHubert2]

AH! David! Thank you so much! These are gorgeous! I just spent the last day trying to get a light streak effect with a bunch of layered cloth sims and it looked *horrible*- these are easy, fast, and look incredible. Thanks again :D

[@davidmcsween]

Squeee. I helped Ian 😁

[@Leo-sd4ps]

When i see IanHubert in the comments, this is quality proof. I mean you help me so much in...like a looot of things, hope one day I will thanks you 😁 properly ! Words of a big fan of yours

[@yesdadbut960]

@@davidmcsween you got the highest honour

[@atch300]

If I’m watching the same tutorials that IanHubert is watching, I know I’m heading in the right direction

[@fhaarkas]

The way it all comes together is pretty much black magic, bro. Thanks for the guide.

[@iReboot42]

Fantastic tutorial David - thanks for uploading. I've been admiring your Blender 'streaks' artwork for some time now - amazing technique.

[@Mr_Vosakisen]

This looks sick!!!! Thank you so much for this

[@NothingHereIsReal]

An excellent explanation, David. I love the results you managed to obtain.

[@matchdance]

Thank you so much! This is the exact effect I am looking for! Amazing tutorial!

[@ChrisAllenMusic]

This is just magical! Thank you for sharing this technique!

[@MissSamGreen]

This was SO helpful! Thank you so much!

[@activemotionpictures]

Super cool! Thank you for sharing!

[@ScarletSnake]

Wow, really cool! This will come in handy in the future, thank you for this tutorial, and subbed! 🙏👏👏👏

[@akshayupadhyay-ir2uw]

woahh i was looking for this exactly, thank you so much man.

[@luculucu10]

Great Tutorial , Thanks

[@blackswan6386]

really helpfull technique and awesome result that i really need for my project ! great work sir, thank you showing your skill, ciao

[@janilsonlima]

Amazing!!!

[@AdamEarleArtist]

Thats so dang pretty

[@davidmcsween]

Thanks Adam, its so easy to make as well

[@MaruHieta]

Learned a lot of new things, thanks for the tut! How can I render a transparent clip?

[@mwauraerick]

Fantastic!

[@davidmcsween]

Thankyou

[@GaryParris]

good work

[@breakstergmr4499]

Nice

[@Will_Scobie]

excellence :)

[@juyounoh7457]

hi thanks for the amazing tutorial it was really nice, Do you know if i can use what i made through this process in unity?

[@user-jy9fr8eg8s]

This is great David! But i find the light streaks are not showing while rendering, can you share your animation rendering settings? It would be helpful. Thanks Daivd!

[@digital0785]

wow it's crazy..... i was working on something today to fake some projector volumetrics similar to this.. but this is arguably a better method.. i really wish blender would make the array modifier actually be instances vs actual individual geometry so it didn't kill performance nearly as much but

[@covertcee]

Very cool and easy to understand. Cheers for that! As a beginner, I'd _love_ to know what expression you'd use to drive the the Z value to reveal the curve. You explain this at 8:34. Would love to animate the 'reveal'. Can't figure out how to elegantly do this.

[@davidmcsween]

You could animate the value of the Map Range node Min value to animate total length reveal as it drives the Alpha

[@ronanm505]

This is exactly what I was looking for, thank you! I've managed to animate the reveal of the curve using the Map Range node, but I can't for the life of me figure out how to hide it again from the opposite end. (ie. I've got the "head" of the light streak to appear like you do in the video, but I want the "tail" to travel along the curve as well so that the streak appears to travel along the path & then disappear. Hope that makes sense!) Do you have any ideas how to achieve this effect?

[@andrewhacker5141]

Between the Map Rage node and the Hue-Saturation-Value node, add a Color Ramp node. In the Colour Ramp node, have three color stops that are ordered black, white, black. You can now keyframe the relative position of these three color stops to animate the appearance/brightness of the light trail from either end of the curve. In addition, if you want to have the light trail completely fade out during the animation there is no way, within the Color Ramp node itself, to animate the color of the middle (white) colour stop to fade to black (AFAIK). To overcome this, add a Maths (Multiply) node betweeen the new Color Ramp node and the Hue-Saturation-Value node. Plug the color from the color ramp into the top socket and set the value of the bottom socket to 1. If you need to fade the light streak out then animate the bottom value to become 0. Hope that helps.

[@ronanm505]

@@andrewhacker5141 Yes, that worked perfectly, THANK YOU! I actually only needed the Colour Ramp node in the end, but good to know about the option of using the Multiply one, in case I need it in another project.

[@BesteAlpkaya]

i get it

[@ianolney3735]

He's cooking

[@nicholaslowe3283]

Thanks David, Is it easy to add a 'color over time' effect to this?

[@hcsmurfje]

Add a driver to the hue color value and use the global variable #frame

[@eternal_aki]

thank you!! is it possible to make this effect on cycles or is it only eevee?

[@davidmcsween]

Sorry this relies on the alpha handling in eevee, you can use cycles but it quickly hits the alpha depth limits causing black to be inserted into the transparent areas

[@HandmadeInJapan]

I love this effect and it's just what I was looking for. Is there a way to do this in cycles too? I keep getting a black box

[@davidmcsween]

To use this in cycles you will have to increase the transparency samples by a LARGE amount. You get that for free in eevee

[@theinkrediblesquid1272]

@@davidmcsween What is the best way to increase the transparency samples for cycles rendering?

[@valovanonym]

@@theinkrediblesquid1272 it's a parameter of the engine

[@Johnwildgoose789]

This is brilliant. If David or anyone else can help me with a novice follow up question - what would be the best way of saving something like this as an animation and then importing it into unity to use within a project there?

[@davidmcsween]

I'm afraid that I don't have any idea about unity but I know that they do volumetric effects realtime and this is effectively a dense card stack with alpha so if you can do many layers of alpha in unity you should be able to make this too

[@Johnwildgoose789]

@@davidmcsween Thanks for coming back to me - its so frustrating! I just followed your tutorial and have made something great (thanks again as I would have had no idea!). When importing into unity it just brings in the shape that would appear in the unrendered view in blender. So I presume there is no way to bring it all in, even if colours/textures are added later in unity - the effect itself is what I'm after. From what you are saying it may be easier to try to create it from scratch in unity?

[@ardiansatriozislamin6590]

amazing tutorial! but how can you make it moves along the path? thank you

[@davidmcsween]

The path animation begins at 7:46" in the video. Otherwise I'm not sure what you mean, sorry

[@the-chameleon]

This is an insanely good tutorial, thanks! Do you have any idea why tilt has disappeared in the N menu for me? Edit: Wasn't in edit mode! Leaving this up for anyone who makes the same mistake as I did.

[@davidmcsween]

Hey I'm glad you found out useful and thanks for the tip. I'm sure others will encounter the same problem

[@AxonMediaSeattle]

Is there a way to animate these in a closed loop? I tried this with a Bezier circle and animating the Z texture mapping value, but it seems like there's a point on the circle where the streak begins and then disappears into. I'm not quite sure why it doesn't go around the curve endlessly.

[@davidmcsween]

You should be able to connect both ends of the curve object together, but you must make sure that the twist angle matches at each end

[@renosnicolaou8417]

how do you render it with transparent? When I render with Film- Transparent in view port in blender i can see but when i am saving png everything is black. Basically in alpha channel everything is black. Thanks

[@davidmcsween]

I'm very sorry to hear that but I cannot see you blender file to know what is wrong. I suggest that you ask for help at blender stackexchange. Good luck. I'm sure you can get it going as others have

[@scyther149]

the 10:40 part don't work for me :c i can't anime the lights... the square it makes purple but when i press play nothing happens

[@jamesbarnardo7496]

EVERY time I save the render result, its a blank render. Any suggestions?

[@davidmcsween]

Does anything appear in the viewport?

[@davidmcsween]

Are you using eevee or cycles? The material is not set up for cycles

[@jamesbarnardo7496]

@@davidmcsween everything looks perfect in the viewport, and even in the render result (I'm using eevee not cycles) but as soon as I save the render result (either an image for an animation frame) the resulting file is a blank image; I've tried with a diffuse plane background, a world background, and a transparent background. My handware is 64gb RAM and RTX 3090, pretty top end PC and I'm definitely no beginner with blender - I've checked all the render settings and updated my studio drivers and downloaded the latest version of blender. I'm at a loss

[@davidmcsween]

@jamesbarnardo7496 what format or codec do you use to save the image? What software do you open the image in to look at it?

[@omaressam4398]

​@@davidmcsween it looks fine and it reneder correct, when export and save it turn completely transparent, i tried png and exr