Allow expressions in brush editor

Not sure if this is even possible, but allowing me to type in an expression, so for example, the value of ‘direction 360’ could be driven by pressure (with maths). This would unlock a whole new odd world of “programmable” brushes.

Mhm, I’m new and don’t even know were to go…


the brush library does not support arbitrary expressions. Basically what you see is what you get in the brush settings panel - the library loads the points in the curve graphs, interpolating them and mapping the inputs to impact the final value of a setting.

While the curves can act as any (limited) approximation of a function, the limitation is that the “functions” are all univariate, and the output only makes up one term in the sum that defines the final setting value.

Having an expression language and multivariate dynamics sounds really interesting. As always with fairly large changes like these, the major hurdle is most likely going to be compatibility and integration into the existing codebase.

Doesn’t look like there’s a way around this being a huge overhaul I’m not experienced enough to even consider. Perhaps a client side virtual setting, which feeds bad data to mypaint based on expressions, but that would be rather limiting .

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