Antimony 0.9.0

News:

This release has a new f-rep parser and a new graph engine!

Not much has changed on the user-facing side of things, but the internals are much spiffier (and will be easier to build on in the future).

New parser

The f-rep parser has been rewritten by @fros1y to use lemon and flex instead of a homebrew solution.

In this rewrite, a second way of expression math was added: infix notation (a.k.a. the way that most people write math). For example, instead of writing

-+qXqYf1

you can write

=pow(X, 2) + pow(Y, 2) - 1;

The leading = and trailing ; indicate to the parser that this is an infix string.

For examples of this new syntax, check out the [cylinder wrap (https://github.com/mkeeter/antimony/blob/develop/py/fab/shapes.py#L804-L824) function.

New graph engine

The graph engine has been rewritten from the ground up as a stand-alone library (though its design is optimized for Antimony's use-case). It no longer uses Qt signals and slots (or at all!), preferring the STL and C++11.

There's a slick re-evaluation optimization: when an upstream object changes, the engine properly sequences downstream update calls to minimize the number of times scripts and datums get re-evaluated. In practice, I've seen a 5x speedup on very large graphs.

Breaking changes:

Some of the changes made here are potentially breaking. There's a transparent migration path from older files; feel free to report bugs if it fails for you.

Namespaces

These changes will be find-and-replaced when older files are loaded, so things should Just Work in most cases.

• fab.ui namespace has been renamed sb.ui
• meta object (which contains export functions) has been renamed sb.export
• fab.color object has been renamed sb.color

Graph changes:

It's no longer legal to connect an output datum to an input in the same script. Previously, this was legal (but a bad idea).

Datums of type str must have their expressions quoted. Previously, there was a magic check to auto-quote them if evaluation failed.

Other features:

• Return key acts like tab when editing datums in an inspector.
• Unary operators (rotate, scale, etc) preserve shape color.
• More information is displayed in viewport (thanks, @joshuashort)
• User data directory is searched for nodes (thanks, @astronouth7303)
• Gradients are calculated exactly (improves rendering quality).
• right_triangle now supports negative widths and heights
• Keyboard arrows (up and down) adjust datum values in inspectors.
• arctan2 operator is now available in f-reps
• Fun new nodes: volume-filling gyroids!

Bugfixes:

• .sb extension is now added on Linux.
• UTF-8 is used regardless of locale settings.

Thanks

Thanks to the following Github users for their contributions, large and small:

• @fros1y
• @joshuashort
• @astronouth7303
• @toomuchcookies
• @neilger
• @defnull