Add raster module to graphene_core

node-graph/gcore/src/lib.rs

@@ -11,6 +11,7 @@ use async_trait::async_trait;
 pub mod generic;
 pub mod ops;
 //pub mod structural;
+pub mod raster;
 pub mod value;
 
 pub trait Node<'n> {

node-graph/gcore/src/raster.rs

@@ -0,0 +1,18 @@
+use core::marker::PhantomData;
+
+use crate::Node;
+
+use self::color::Color;
+
+pub mod color;
+
+pub struct GrayscaleNode<'n, N: Node<'n, Output = Color>>(pub N, PhantomData<&'n ()>);
+
+impl<'n, N: Node<'n, Output = Color>> Node<'n> for GrayscaleNode<'n, N> {
+	type Output = Color;
+	fn eval(&'n self) -> Color {
+		let color = self.0.eval();
+		let avg = (color.r() + color.g() + color.b()) / 3.0;
+		Color::from_rgbaf32(avg, avg, avg, color.a()).expect("Grayscale node created an invalid color")
+	}
+}

node-graph/gcore/src/raster/color.rs

@@ -0,0 +1,173 @@
+use serde::{Deserialize, Serialize};
+
+/// Structure that represents a color.
+/// Internally alpha is stored as `f32` that ranges from `0.0` (transparent) to `1.0` (opaque).
+/// The other components (RGB) are stored as `f32` that range from `0.0` up to `f32::MAX`,
+/// the values encode the brightness of each channel proportional to the light intensity in cd/m² (nits) in HDR, and `0.0` (black) to `1.0` (white) in SDR color.
+#[repr(C)]
+#[derive(Debug, Clone, Copy, PartialEq, Default, Serialize, Deserialize)]
+pub struct Color {
+	red: f32,
+	green: f32,
+	blue: f32,
+	alpha: f32,
+}
+
+impl Color {
+	pub const BLACK: Color = Color::from_unsafe(0., 0., 0.);
+	pub const WHITE: Color = Color::from_unsafe(1., 1., 1.);
+	pub const RED: Color = Color::from_unsafe(1., 0., 0.);
+	pub const GREEN: Color = Color::from_unsafe(0., 1., 0.);
+	pub const BLUE: Color = Color::from_unsafe(0., 0., 1.);
+
+	/// Returns `Some(Color)` if `red`, `green`, `blue` and `alpha` have a valid value. Negative numbers (including `-0.0`), NaN, and infinity are not valid values and return `None`.
+	/// Alpha values greater than `1.0` are not valid.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgbaf32(0.3, 0.14, 0.15, 0.92).unwrap();
+	/// assert!(color.components() == (0.3, 0.14, 0.15, 0.92));
+	///
+	/// let color = Color::from_rgbaf32(1.0, 1.0, 1.0, f32::NAN);
+	/// assert!(color == None);
+	/// ```
+	pub fn from_rgbaf32(red: f32, green: f32, blue: f32, alpha: f32) -> Option<Color> {
+		if alpha > 1. || [red, green, blue, alpha].iter().any(|c| c.is_sign_negative() || !c.is_finite()) {
+			return None;
+		}
+		Some(Color { red, green, blue, alpha })
+	}
+
+	/// Return an opaque `Color` from given `f32` RGB channels.
+	pub const fn from_unsafe(red: f32, green: f32, blue: f32) -> Color {
+		Color { red, green, blue, alpha: 1. }
+	}
+
+	/// Return an opaque SDR `Color` given RGB channels from `0` to `255`.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgb8(0x72, 0x67, 0x62);
+	/// let color2 = Color::from_rgba8(0x72, 0x67, 0x62, 0xFF);
+	/// assert!(color == color2)
+	/// ```
+	pub fn from_rgb8(red: u8, green: u8, blue: u8) -> Color {
+		Color::from_rgba8(red, green, blue, 255)
+	}
+
+	/// Return an SDR `Color` given RGBA channels from `0` to `255`.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgba8(0x72, 0x67, 0x62, 0x61);
+	/// ```
+	pub fn from_rgba8(red: u8, green: u8, blue: u8, alpha: u8) -> Color {
+		let map_range = |int_color| int_color as f32 / 255.0;
+		Color {
+			red: map_range(red),
+			green: map_range(green),
+			blue: map_range(blue),
+			alpha: map_range(alpha),
+		}
+	}
+
+	/// Return the `red` component.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgbaf32(0.114, 0.103, 0.98, 0.97).unwrap();
+	/// assert!(color.r() == 0.114);
+	/// ```
+	pub fn r(&self) -> f32 {
+		self.red
+	}
+
+	/// Return the `green` component.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgbaf32(0.114, 0.103, 0.98, 0.97).unwrap();
+	/// assert!(color.g() == 0.103);
+	/// ```
+	pub fn g(&self) -> f32 {
+		self.green
+	}
+
+	/// Return the `blue` component.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgbaf32(0.114, 0.103, 0.98, 0.97).unwrap();
+	/// assert!(color.b() == 0.98);
+	/// ```
+	pub fn b(&self) -> f32 {
+		self.blue
+	}
+
+	/// Return the `alpha` component without checking its expected `0.0` to `1.0` range.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgbaf32(0.114, 0.103, 0.98, 0.97).unwrap();
+	/// assert!(color.a() == 0.97);
+	/// ```
+	pub fn a(&self) -> f32 {
+		self.alpha
+	}
+
+	/// Return the all components as a tuple, first component is red, followed by green, followed by blue, followed by alpha.
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgbaf32(0.114, 0.103, 0.98, 0.97).unwrap();
+	/// assert!(color.components() == (0.114, 0.103, 0.98, 0.97));
+	/// ```
+	pub fn components(&self) -> (f32, f32, f32, f32) {
+		(self.red, self.green, self.blue, self.alpha)
+	}
+
+	// TODO: Readd formatting
+
+	/// Creates a color from a 8-character RGBA hex string (without a # prefix).
+	///
+	/// # Examples
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgba_str("7C67FA61").unwrap();
+	/// ```
+	pub fn from_rgba_str(color_str: &str) -> Option<Color> {
+		if color_str.len() != 8 {
+			return None;
+		}
+		let r = u8::from_str_radix(&color_str[0..2], 16).ok()?;
+		let g = u8::from_str_radix(&color_str[2..4], 16).ok()?;
+		let b = u8::from_str_radix(&color_str[4..6], 16).ok()?;
+		let a = u8::from_str_radix(&color_str[6..8], 16).ok()?;
+
+		Some(Color::from_rgba8(r, g, b, a))
+	}
+
+	/// Creates a color from a 6-character RGB hex string (without a # prefix).
+	/// ```
+	/// use graphene_core::raster::color::Color;
+	/// let color = Color::from_rgb_str("7C67FA").unwrap();
+	/// ```
+	pub fn from_rgb_str(color_str: &str) -> Option<Color> {
+		if color_str.len() != 6 {
+			return None;
+		}
+		let r = u8::from_str_radix(&color_str[0..2], 16).ok()?;
+		let g = u8::from_str_radix(&color_str[2..4], 16).ok()?;
+		let b = u8::from_str_radix(&color_str[4..6], 16).ok()?;
+
+		Some(Color::from_rgb8(r, g, b))
+	}
+}