Struct EditorScale 

pub struct EditorScale { /* private fields */ }

Shared, mutable editor scale factor.

Single source of truth for the live content-scale of an open plugin window. Each GUI backend (egui / iced / slint) constructs one in Editor::open, stores it on the editor for set_scale_factor to write through, and hands a clone to its baseview WindowHandler so the render thread can pick up changes between frames.

Two writers, one reader-per-frame:

• Editor::set_scale_factor (host → editor, e.g. CLAP set_scale, VST3 Windows IPlugViewContentScaleSupport).
• WindowEvent::Resized (baseview → handler, fired when the OS reports a new content scale, e.g. dragging the window across monitors with different DPIs).

Most-recent-write wins. The handler tracks a last_applied_scale alongside its EditorScale clone and, when it observes a divergence at frame start, recomputes physical sizes and reconfigures its surface / renderer.

Implementations

impl EditorScale

pub fn new(initial: f64) -> Self

Construct with an initial scale. Non-finite or non-positive values clamp to 1.0 so callers never have to defend against 0.0 * size collapsing the surface.

pub fn get(&self) -> f64

Read the current scale.

pub fn get_f32(&self) -> f32

Read the current scale, narrowed to f32 for renderer / DSP use. Display scales never exceed 4.0 in practice, so the f64 → f32 narrowing is invisible.

pub fn set(&self, scale: f64)

Update the current scale. Non-finite or non-positive values are silently dropped - callers are forwarding numbers from hosts / info.scale() where a bad value is a host bug, not something to propagate into the surface config.

pub fn take_change(&self, last: &mut f32) -> Option<f32>

Pick up a host-driven scale change since the last frame.

Reads the current scale (narrowed to f32) and compares it bit-identically against last. When the value moved, updates last and returns Some(cur); otherwise returns None.

Used by every editor backend’s per-frame loop to gate surface / renderer reconfiguration on actual host scale events. Bit-equality is the correct semantics - the cell is written verbatim from host callbacks, never through accumulating arithmetic, so an epsilon-based check would either thrash on noise (there is none) or miss a legitimate 1.0 → 1.0001 host signal.

Trait Implementations

impl Clone for EditorScale

fn clone(&self) -> EditorScale

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.