Struct ResolutionContext 

pub struct ResolutionContext {
    pub element_font_size: f32,
    pub parent_font_size: f32,
    pub root_font_size: f32,
    pub containing_block_size: PhysicalSize,
    pub element_size: Option<PhysicalSize>,
    pub viewport_size: PhysicalSize,
}

Context information needed to properly resolve CSS units (em, rem, %) to pixels.

This struct contains all the contextual information that PixelValue::resolve() needs to correctly convert relative units according to the CSS specification:

• em units: For most properties, em refers to the element’s own computed font-size. For the font-size property itself, em refers to the parent’s computed font-size.

• rem units: Always refer to the root element’s computed font-size.

• % units: Percentage resolution depends on the property:

  • Width/height: relative to containing block dimensions
  • Margin/padding: relative to containing block width (even top/bottom!)
  • Border-radius: relative to element’s own border box dimensions
  • Font-size: relative to parent’s font-size

Fields

element_font_size: f32

The computed font-size of the current element (for em in non-font properties)

parent_font_size: f32

The computed font-size of the parent element (for em in font-size property)

root_font_size: f32

The computed font-size of the root element (for rem units)

containing_block_size: PhysicalSize

The containing block dimensions (for % in width/height/margins/padding)

element_size: Option<PhysicalSize>

The element’s own border box size (for % in border-radius, transforms) May be None during first layout pass before size is determined

viewport_size: PhysicalSize

The viewport size in CSS pixels (for vw, vh, vmin, vmax units) This is the layout viewport size, not physical screen size

Implementations

impl ResolutionContext

pub const fn default_const() -> Self

Create a minimal context for testing or default resolution

pub const fn for_fonts( element_font_size: f32, parent_font_size: f32, root_font_size: f32, ) -> Self

Create a context with only font-size information (for font-relative units)

pub const fn with_containing_block( self, containing_block_size: PhysicalSize, ) -> Self

Create a context with containing block information (for percentage units)

pub const fn with_element_size(self, element_size: PhysicalSize) -> Self

Create a context with element size information (for border-radius, transforms)

pub const fn with_viewport_size(self, viewport_size: PhysicalSize) -> Self

Create a context with viewport size information (for vw, vh, vmin, vmax units)

Trait Implementations

impl Clone for ResolutionContext

fn clone(&self) -> ResolutionContext

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ResolutionContext

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

Formats the value using the given formatter.

impl Default for ResolutionContext

fn default() -> Self

Returns the “default value” for a type.

impl Copy for ResolutionContext