Vector Drawing with Pen Pressure or Radius

[ShenCiao]

Do you know any other vector drawing datasets that include pen pressure or radius data except for what I've listed on the tutorial?
Tell me and I will add link to them.

[pluskid]

Are there existing program or app that can be used to collect such a dataset by drawing / sketching?

[ShenCiao]

As far as I know, there isn't an out-of-the-box solution for such task. Although teams behind the OpenSketch, Tracing-vs-freehand already collect such data, they didn't open-source their tools.

If you don't resist to learn, I would recommend write a Blender Grease Pencil add-on. It's well-established for many years and has many tools to edit such data structure. My project Ciallo use the trick when it's not capable of producing drawings.

[pluskid]

What data format are those test sets in? For example, can you take a vector drawing tool, do a sketch, and export it in svg format. Would there be information for each stroke with pressure sensitivity information?

[ShenCiao]

There isn't a standard format for now. I know Tracing-vs-freehand dataset is stored in a database.

For sure, a standard data format such as SVG is necessary in the future, but SVG cannot support it since SVG's <polyline> element don't support variable width. As for my own project, I use csv files to store a drawing with hundreds of strokes. The csv files have three columns, representing positionX, positionY, and pen pressure, each row is a point or leave a blank row for the stroke end.

[pluskid]

Ah, I see. That's a good point, there is a lot of other meta data such as the orientation of the stylus which will determine the orientation of the stamps for many digital brushes. After a bit looking up, it turns out that Wacom has a so called universal ink model which defines some "standard" data format for storing such stroke information. Though I'm not sure if any existing software is using this data format.