Gain (vizia)

The gain plugin reimplemented with a Vizia GUI. Same DSP as the built-in gain example, different frontend.

Source: crates/truce-vizia/examples/truce-example-gain-vizia/.

#What it demonstrates

ViziaEditor with a setup closure receiving &mut Context + ParamLens<P>
param_knob, param_xy_pad, level_meter widget helpers
Shared Signal<f32> per param — knob and XY pad bound to the same id stay in sync without extra wiring
Per-OS screenshot baselines with pixel_threshold(2) on Linux and Windows (rasterizer drift)
with_stylesheet(widgets::BASE_CSS) for vizia layout shims
with_font(JETBRAINS_MONO) for cross-backend visual parity

#Layout

Left column: two knobs (Gain, Pan) over a 130×130 Pan/Gain XY pad. Right column: stereo meter spanning the full height. 176×260 logical points, aligned so the XY pad's bottom edge matches the meter's.

#Files

src/lib.rs — plugin logic, editor wiring, screenshot tests
src/main.rs — standalone host entry point

#See also

vizia integration guide
gain — same plugin with the built-in GUI
gain-egui — same plugin with egui
gain-iced — same plugin with iced
gain-slint — same plugin with slint

#Build and test

cargo build --manifest-path crates/truce-vizia/Cargo.toml \
    -p truce-example-gain-vizia
cargo test --manifest-path crates/truce-vizia/Cargo.toml \
    -p truce-example-gain-vizia

The vizia examples live in a separate Cargo sub-workspace (see the vizia integration guide for why). All cargo build / cargo test invocations need --manifest-path crates/truce-vizia/Cargo.toml.