Add C# version of TiltBrushToolkit

[Prystopia]

Direct copy of python tools in C# covering parsing and writing .tilt files and parsing .json Tilt Brush export files.

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[Prystopia]

I signed it

[dubois]

Hi. Thank you for the contribution! Unfortunately, we don't have the staffing to code-review and support new 3rd party code. Please consider forking instead.

[andybak]

Actually - this would probably be better placed in a separate repo.

(However - note to the dev team. This isn't giving out a terribly positive signal about the future of this project - activity across Google VR has been pretty quiet for months. Is it time to move on?)

[Prystopia]

Hi, I understand, it was a big piece of work to be checked through, thank you for your time.

I have uploaded the project into a new repo, which can be found here

[andybak]

The potential of this is huge. You could create a tool to algorithmically create or modify Tilt Brush files.

Imagine saving a piece of work, opening up a second (VR or non-VR) app and having a bunch of "filters" you could apply to manipulate the brush strokes. It's obviously not quite as cool as having a plugin architecture within Tilt Brush itself but it's still a fairly powerful way of extending the core functionality.

[Prystopia]

Yeah, the project was created for use within my Masters thesis, which did exactly that, using evolutionary algorithms to create and amend Tilt Brush models, you can create some really cool pieces of art.

[n1ckfg]

That sounds amazing--have you posted the results anywhere?

[Prystopia]

Thank you, no not yet, I am hoping to get something set up within the next week, but I'll reply to this thread as soon as it's live.

[dubois]

Regarding algorithmic modification of Tilt Brush sketches, we just released an Artist in Residence project called A Show of Kindness on Steam.

It uses a technique where the tilt is exported to USD (which the lastest TB supports now). USD is a Pixar format gaining traction in the 3d industry, and it has robust scripting and tooling support. The USD we export contains all the information from the .tilt as well as the fbx.

Jeremy Cowles (who was also the designer of USD) manipulated the USD scene to modify stroke timings and such, then imported it back into a new Unity project using USD.NET, which he wrote and made available on GitHub.

Personally, I think this approach is the correct one; rather than try to add another file format into the ecosystem, Tilt Brush should export to existing formats. It's just that before USD, there was no good candidate.

Looking forward to hearing more about your project!

[n1ckfg]

Wow, I had no idea that USD could support a displaying sequence of brushstrokes in a standardized way. (I've used hide or scale keyframes for exchange before, but I find those aren't interpreted consistently across different apps.)

That said, I do find tilt files are an efficient way to preserve the original stroke information--is there a way to generate a tilt file from scratch in the Python sdk, the way @Prystopia does with C#? I've got tilt import support in my Blender Grease Pencil plugin, but no export because all the code examples I've seen assume you're modifying an existing tilt file. (I've tried some permutations of Tilt() and Sketch() with no luck.)

[Prystopia]

Hi everyone, I've finally gotten around to writing an overview of the project which can be found here.