# How to move a particle emitting object around a movie clip in Blender?

just wondering if we can move a particle emitting object around a video clip in Blender without using a plane with video texture. Please find a sample image below. You may also find this video for a better idea of what I am trying to achieve.

• What is your goal? Is there something specific in a process that interest you? Like - do you want to work with VSE "movie clip" in 3D viewport because of tools that are accesible only from VSE? I don't see a reason why one would do that? Thank you – vklidu Dec 10 '19 at 17:22
• For 2.7x there was a script that took VSE strip to Node Compositor, so probably it is possible to write a scrit that sends strip (instead to compositor) to shading nodes. Like that you would be able assign movie clip nested in material to a plane in 3dviewport ... – vklidu Dec 10 '19 at 17:44
• Hi @vklidu, thank you for the response. I am trying to wrap a sparkle animation, just like fairy dust, around a video footage. I can apply the video texture on a plane and then rotate the particle around it. But that deteriorates the quality of the video footage. There can be many other scenarios where this can be useful. – subratabera Dec 11 '19 at 16:55
• Probably my low knowledge, but what I know any app combines 2D with 3D by switching into 3D scene and does composite in the same way like blender does - takes video clip as a texture on plane. I will try to post an example - so if you can see some deterioration.Or do you have some example from others? – vklidu Dec 11 '19 at 17:18

## version Plane in 3D Scene

You didn't ask for it, but what I know all comp. apps works in that way, with the same amounth of "deterioration" a quality of the video footage - all apps operates with a video texture on a plane in 3D scene.

Simplified – If you connect a Texture node (with video sequence) directly into output (without shader) than colour information stay the same.

In Color Management switch from Filmic to Standard.

What I would miss in this case, are matte tools. Sorry for dirty way I found on the way (probably exists better), or you should separate foreground in compositor properly, render it with alpha and use this image sequence, but that's another topic.

Example with particles. GreenScren is taken from internet, easily find by name (Green Screen Sample | Panasonic HMC150).

Example with Smoke Simulation. GIF compression is too much here I will try post regular render later.

## version Composite

Another way (without Plane in 3D scene) is Composite - to render Smoke separately with faked Z pass in RenderLayer (in this case simple greyscale gradient texture) because blender doesn't handle volumetric depth and even if you want to emit smoke like a particles (plane with texture) Z pass does not handle transparency as well.

Smoke for this version you can render from blend above, but not as Render output, but enable Composite first (and delete or exclude plane from rendering). If you switch layout to Compositing you will se two Render Layers - one is regular render, second with faked Zpass.

These images has to be saved as OpenEXR_Multilayer (32-bit) file format, so you would be able get enough depth data to composite plane. I expected much worse result, but for smoke type worked quite well :) Smoke was rendered only with 6 samples = noisy, but expect some noise in composite anyway. These even smooth anti-aliased pixels will be used as depth data, which means - any pixel represents position in - depth (little confusing call this Z pass in blender terminology where depth from front view is Y axis :), forget it. So in this level there is not any anti-aliasing (if I'm correct).

Result (also because of gif commpresion) is not fair, I probably changed some parameter for smoke material due testing mishmash.

For compositing is here is essential Z Combine node that is responsible for mixing depth data. Because video doesn§t have any depth info and we need to place it similar to 3Dscene it's enough to set to the actor some grey value for Z input. If you try to move slider to white or black you will se how smoke is appears forward or backward of actor.

• Looks like even alpha from "Smoke Depth" render layer can do a good job. Colored for fun.
• Thank you very much @vklidu. You are amazing!! That is exactly what I was looking for. I am sure with time Blender will add many more composition features which will make it even more powerful. – subratabera Dec 12 '19 at 7:59
• By the way, I tried the first version of the answer. I am still a bit new to Blender to try the second solution. :) – subratabera Dec 14 '19 at 5:55
• Thats an answer for my Q :-) can we delete all the comments here? They are in purpose of exploring issue rather than chatting. BTW second version interest me as well, I will extend the answer with test file and artefacts that comes with it. To generate smoke like in video you probably already found a way blender.stackexchange.com/questions/33520/… – vklidu Dec 14 '19 at 6:04
• Indeed. That's the exact method I followed for the smoke effect. Though I am also trying various particle simulations with Eevee. Thanks again for the link. – subratabera Dec 14 '19 at 9:14