Enum DropoutControl 

pub enum DropoutControl {
    Ignore,
    Simple,
    SimpleWithStubs,
    Smart,
    SmartWithStubs,
}

The dropout control mode for a bilevel rasterizer.

Dropout control defines how to treat features too thin to register on the pixel grid. A TrueType glyph program selects the mode with the SCANCTRL and SCANTYPE instructions, and may select a different mode for each glyph. It affects only rasterization to one bit per pixel. An antialiasing rasterizer uses coverage and does not need it.

See https://learn.microsoft.com/en-us/typography/opentype/spec/tt_instructions#scan-conversion-control.

Variants

Ignore

Fills only pixels whose centers are covered. Thin features may vanish.

Simple

Restores a dropped feature that crosses a scan line, ignoring stubs.

This is the default when a glyph program does not set a mode.

SimpleWithStubs

Like Self::Simple, but also restores stubs.

Smart

Restores a dropped feature at the best position chosen by the scan converter rather than a fixed one, ignoring stubs.

SmartWithStubs

Like Self::Smart, but also restores stubs.

Implementations

impl DropoutControl

pub fn is_enabled(self) -> bool

Returns true if dropped features should be restored.

pub fn is_smart(self) -> bool

Returns true if the scan converter should choose the restore position.

pub fn includes_stubs(self) -> bool

Returns true if stubs should be restored along with crossing features.

Trait Implementations

impl Clone for DropoutControl

fn clone(&self) -> DropoutControl

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for DropoutControl

impl Debug for DropoutControl

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for DropoutControl

fn default() -> DropoutControl

Returns the “default value” for a type.

impl Eq for DropoutControl

impl PartialEq for DropoutControl

fn eq(&self, other: &DropoutControl) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for DropoutControl