IDEA : Water effect

[leoceto]

Not an issue but more a food for thoughts.

In south Korea, this is a building with a led wall showcasing some water waves in a cube : https://www.youtube.com/watch?v=eoLA0lUEaF8&ab_channel=SurferToday

I was wondering if we could set up the same kind of effect on the cube? Maybe leveraging a video of scene we create in Blender like this one ? https://www.youtube.com/watch?v=3EfgsciQ5rM&ab_channel=LawrenceJaeger

What do you think ? Even if the resolution won't be obvioulsy the same, it could be awesome !

[Staacks]

The good news is that playing video is possible. At an early stage I have tested a bunch of animated GIFs which you can simply play back with one of the examples in the rgb matrix library (see for example here: https://twitter.com/diconx/status/1251803926741094400). I had a little imagemagick command to get a proper projection and if I remember correctly, the example from the library needed to decode the provided GIF first into a raw format before playing it back, but unless it is a too long loop, it should work.

However, the projection is the problem. I have seen several videos like the one you shared and I until I have seen something like this in reality, I am very sure that this only works on video and they only pull this off to share it on social media. The thing is that the perspective will only work from exactly one point of view. If you are looking from just a slightly different angle, the animation will no longer match the orientation of the cube. I am convinced that (while the building certainly still looks cool) the depth illusion of looking into the building is not working for anyone who is in any other location than the camera.

For the cube, stereoscopic sight might also be a problem. A large scale installation like this building might get away with it as everything is so far away that there is no noticable parallax. But a cube right in front of you will certainly still look rather flat. Not to say that it would not look nice, but I would not expect that it would have this depth illusion unless filmed (no stereoscopy) from a fixed position (aligned with the rendered perspective).

Still, if you want to try it: Render an animation and run it through the example from the matrix library. Let me know if you need help with the projection (since the panels in my version of the cube are rotated, you probably cannot set this up in Blender directly, but need to reproject).

[Staacks]

BTW: I closed it as it is not an issue. Feel free to discuss here. If you create anything in this direction I would love to hear about it :)

[leoceto]

Thanks for the extanded answer, I will try to do some thing and keep you posted. Could you share the code you use for this ? https://twitter.com/diconx/status/1251803926741094400

By the way, you should try to open a channel to open communication on your project (either as comments in your blog or a forum or a reddit), as GITHUB is not really the best platform for that !

[Staacks]

This is a GIF I found somewhere on the web. I played it back with "led-image-viewer" found in the "utils" folder of the library. The tricky part is mapping it to the cube, which I did with the following script using imagemagick:

convert "$1" -coalesce -resize 1000x1000^ +distort Affine '0,250 0,64  0,750 64,64  500,500 0,0' -crop 64x64+0+0 +repage "$2.1.gif"
convert "$1" -coalesce -resize 1000x1000^ +distort Affine '500,500 64,0  1000,250 128,0  1000,750 128,64' -crop 64x64+64+0 +repage "$2.2.gif"
convert "$1" -coalesce -resize 1000x1000^ +distort Affine '0,250 192,0  500,0 192,64  500,500 128,0' -crop 64x64+128+0 +repage "$2.3.gif"
convert "$2.1.gif" -repage 192x64 -coalesce null: \( "$2.2.gif" -coalesce \) -geometry +64+0 -layers composite null: \( "$2.3.gif" -coalesce \) -geometry +128+0 -layers composite "$2"
rm "$2.1.gif"
rm "$2.2.gif"
rm "$2.3.gif"

You simply call with input file as first parameter and the destination as second parameter.

About the discussion: I see your point. When I created the blog I wanted just a static page to share my stuff without much effort. For me this is mostly about giving back to the open source community for all the things I learned from other open projects. I do not want to manage a non-static website and I want to be able to simply ignore this hobby for a while if my family and/or my job are a bit more demanding - so I did not really expect so much feedback.

Well, I have now created https://www.reddit.com/r/thereoughtabe - I will link to it the next time I update my page. Let's see where this goes. :)

[leoceto]

Thanks I will use the REDDIT for futher discussion. Your script is awesome to put GIF on the cube. I used it on the following gif https://giphy.com/gifs/space-pixel-art-planet-l3978y5HqiEtqupiM
and the result is incredibly nice with a kind of 3D effect !!!!!