Struct EmissiveMaterial 

pub struct EmissiveMaterial {
    pub emissive_color: LinearRgba,
    pub intensity: f32,
    pub alpha_mode: AlphaMode,
}

A material that emits light without being affected by scene lighting.

Emissive materials are perfect for objects that should glow or appear self-illuminated, such as neon signs, magical effects, UI elements, LED displays, or light sources. They render at full brightness regardless of lighting conditions.

HDR Support

The intensity parameter allows values greater than 1.0, enabling High Dynamic Range (HDR) emissive effects. This is particularly useful for bloom post-processing effects where bright emissive surfaces can “bleed” light into surrounding areas.

Examples

use khora_core::asset::EmissiveMaterial;
use khora_core::math::LinearRgba;

// Create a bright red glowing sign
let neon_sign = EmissiveMaterial {
    emissive_color: LinearRgba::new(1.0, 0.0, 0.0, 1.0),
    intensity: 2.0,  // HDR intensity for bloom
    ..Default::default()
};

// Create a subtle blue glow
let subtle_glow = EmissiveMaterial {
    emissive_color: LinearRgba::new(0.3, 0.5, 1.0, 1.0),
    intensity: 0.5,
    ..Default::default()
};

Fields

emissive_color: LinearRgba

The emissive color of the material.

This color is directly output to the framebuffer without any lighting calculations. The RGB values represent the color of the emitted light.

intensity: f32

Optional texture for emissive color.

If present, the texture’s RGB values are multiplied with emissive_color. The alpha channel can be used for transparency when combined with appropriate alpha_mode.

Future work: Texture asset system integration pending. Intensity multiplier for the emissive color.

Values greater than 1.0 enable HDR effects and are particularly useful for bloom post-processing. A value of 1.0 produces standard emissive output.

Recommended ranges:

• 0.0-1.0: Subtle emission
• 1.0-3.0: Strong emission with bloom
• 3.0+: Very bright, suitable for light sources

alpha_mode: AlphaMode

The alpha blending mode for this material.

Determines how transparency is handled. See AlphaMode for details.

Trait Implementations

impl Clone for EmissiveMaterial

fn clone(&self) -> EmissiveMaterial

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EmissiveMaterial

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

Formats the value using the given formatter.

impl Default for EmissiveMaterial

fn default() -> Self

Returns the “default value” for a type.

impl Material for EmissiveMaterial

fn base_color(&self) -> LinearRgba

Returns the base color (albedo or diffuse) of the material. Default implementation is White.

fn emissive_color(&self) -> LinearRgba

Returns the emissive color of the material. Default implementation is Black.

fn specular_power(&self) -> f32

Returns the specular power or roughness conversion for the material. Default implementation is 32.0.

fn ambient_color(&self) -> LinearRgba

Returns the ambient color modifier for the material. Default implementation is (0.1, 0.1, 0.1, 0.0).

impl Asset for EmissiveMaterial