Mancini API Reference

Mancini is mazarin’s UI toolkit — the interactor library that every application uses for layout, drawing, theming, and neumorphic rendering.

Tutorials

• Constraints — build a small app that demonstrates constraint-driven layout, custom .vgo programs, and reactive updates

Packages

Package	Description
mancini	Core interfaces and types: layout attributes, draw context, theme, palette, neumorphic parameters
mancini/impl	Base “classes” for concrete interactors: Interactor, ThemedInteractor, Parent, Decorator
mancini/std	Standard interactor catalog: Button, Label, Column, Row, AppWindow, and more
mancini/theme	Default implementations of Theme, Palette, and NeumorphicParams

Architecture at a Glance

Mancini layers object-oriented interactor design onto Go’s struct embedding. The key concepts:

• Backpointer pattern — every interactor stores a reference to its outermost concrete type, enabling virtual dispatch through the embedding chain. See impl for details.

• Constraint-driven layout — position and size come from a global constraint network, not from preferred-size methods. Parent-child relationships are discovered through constraint attributes.

• Neumorphic rendering — three depth states (Raised, Flush, Inset) with shadow parameters delivered through the Theme. All interactors handle nil parameters gracefully, falling back to flat drawing.

• DrawContext — all rendering goes through a thin interface wrapping fogleman/gg. Interactors that need features not in the interface (arc fills, clipping) use local buffers and composite via image/draw.