Struct LcdMaskBuilder 

pub struct LcdMaskBuilder { /* private fields */ }

Accumulator for an LcdMask. Build the gray buffer with one or more with_paths calls (each opens an AGG rasterizer scope), then finalize to apply the 5-tap filter and produce the packed mask.

Implementations

impl LcdMaskBuilder

pub fn new(mask_w: u32, mask_h: u32) -> Self

Allocate a zeroed builder for an mask_w × mask_h output mask. The internal gray buffer is (3 × mask_w) × mask_h bytes.

pub fn with_clip(self, clip: Option<(f64, f64, f64, f64)>) -> Self

Set a clip rectangle in screen-space (mask pixel coords). All subsequent with_paths calls render only inside the clip; pixels outside it stay zero in the gray buffer (and therefore produce zero coverage in the final filtered mask). Builder-style; chain after new.

pub fn with_paths<F>(&mut self, transform: &TransAffine, f: F)

where F: FnOnce(&mut dyn FnMut(&mut PathStorage)),

Open an AGG rasterizer scope and let f add as many paths as it likes via the supplied &mut FnMut(&mut PathStorage). All paths share transform, with X supersampled by 3 inside the scope. Lifetimes prevent us from keeping the renderer alive across separate method calls (it borrows self.gray), so the closure pattern scopes the borrow precisely.

pub fn finalize(self) -> LcdMask

Apply the 5-tap low-pass filter to the gray buffer and return the packed mask. Consumes the builder; callers usually composite the result via LcdBuffer::composite_mask or composite_lcd_mask.