Enum Material 

pub enum Material {
    Opaque,
    Glass {
        blur_radius: f32,
        depth_index: u32,
    },
    Overlay,
    Multiply,
    Screen,
    BlendOverlay,
    Darken,
    Lighten,
    ColorDodge,
    ColorBurn,
    HardLight,
    SoftLight,
    Difference,
    Exclusion,
    Hue,
    Saturation,
    Color,
    Luminosity,
    Isolated,
    ShaderEffect {
        effect_name: String,
        params_json: String,
    },
}

Material type that determines which GPU pass a layer’s draw calls are routed to in the Backdrop Capture Architecture.

The blend mode variants correspond to the 16 SVG 1.1 blend modes from the CSS Compositing and Blending Level 1 specification. When a blend mode is set, the draw call’s fragment shader uses the corresponding blend function instead of standard alpha compositing.

Isolated triggers off-screen buffer rendering: the layer and all its children are rendered to a separate texture, then composited back into the main scene. This matches the SVG isolation property.

Variants

Opaque

Opaque or standard UI. Rendered in the initial Scene Capture pass with standard alpha compositing (src-over).

Glass

Glassmorphism elements. Rendered in the Material Composite pass, sampling from the Kawase Blur pyramid. The blur_radius controls the blur intensity. The depth_index (0=foreground, higher=more background) controls depth-aware tinting: background windows get stronger tint.

Fields

blur_radius: f32

depth_index: u32

Z-order depth for depth-aware tinting. 0 = key/foreground window. Higher values = more background. Default: 0.

Overlay

Overlay UI (crisp text, focus rings, edge lighting). Rendered in the final Foreground pass, on top of glass.

Multiply

Multiplied blend: multiplies source and destination colors. Formula: result = src * dst

Screen

Screen blend: inverse of multiply. Formula: result = 1 - (1 - src) * (1 - dst)

BlendOverlay

Overlay blend: combines multiply and screen based on destination. Formula: if dst < 0.5 then 2srcdst else 1-2*(1-src)*(1-dst)

Darken

Darken blend: keeps the darker of source and destination per channel. Formula: result = min(src, dst)

Lighten

Lighten blend: keeps the lighter of source and destination per channel. Formula: result = max(src, dst)

ColorDodge

Color-dodge blend: brightens destination to reflect source. Formula: result = dst / (1 - src)

ColorBurn

Color-burn blend: darkens destination to reflect source. Formula: result = 1 - (1 - dst) / src

HardLight

Hard-light blend: like overlay, but based on source instead of dest. Formula: if src < 0.5 then 2srcdst else 1-2*(1-src)*(1-dst)

SoftLight

Soft-light blend: subtle highlights/shadows. Formula: result = (1-2src)dst^2 + 2srcdst (simplified Pegtop)

Difference

Difference blend: subtracts colors and takes absolute value. Formula: result = |src - dst|

Exclusion

Exclusion blend: similar to difference but lower contrast. Formula: result = src + dst - 2srcdst

Hue

Hue blend: applies source hue to destination saturation/luminosity.

Saturation

Saturation blend: applies source saturation to destination hue/luminosity.

Color

Color blend: applies source hue/saturation to destination luminosity.

Luminosity

Luminosity blend: applies source luminosity to destination hue/saturation.

Isolated

Isolated rendering: layer and children are rendered to an off-screen buffer, then composited back into the main scene. This matches the SVG isolation property and is required for correct blend mode behavior when child elements should not blend with the background.

ShaderEffect

Renders the layer and its children into an offscreen buffer, then applies a custom post-processing WGSL shader when blending back into the scene.

Fields

effect_name: String

Name of the registered shader effect (e.g. “HeatShimmer”)

params_json: String

Dynamic parameters for the shader, serialized as a JSON string

Trait Implementations

impl Clone for Material

fn clone(&self) -> Material

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Material

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

Formats the value using the given formatter.

impl Default for Material

fn default() -> Material

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Material

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Material

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Material

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Material