From 366906b956ecbf918533450b0c9def86442e2874 Mon Sep 17 00:00:00 2001
From: Dennis Kobert <dennis@kobert.dev>
Date: Sun, 23 Apr 2023 19:42:34 +0200
Subject: [PATCH] Add Luma struct (#1154)

* Make Luma usable for MaskImageNode
---
 node-graph/gcore/src/raster.rs                |  2 +-
 node-graph/gcore/src/raster/color.rs          | 28 +++++++++++++++++++
 .../interpreted-executor/src/node_registry.rs |  1 +
 3 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/node-graph/gcore/src/raster.rs b/node-graph/gcore/src/raster.rs
index 70b8cb7f2..41cac43fc 100644
--- a/node-graph/gcore/src/raster.rs
+++ b/node-graph/gcore/src/raster.rs
@@ -9,7 +9,7 @@ use num_traits::{cast::cast as num_cast, Num, NumCast};
 #[cfg(target_arch = "spirv")]
 use spirv_std::num_traits::{cast::cast as num_cast, float::Float, FromPrimitive, Num, NumCast, ToPrimitive};
 
-pub use self::color::Color;
+pub use self::color::{Color, Luma};
 
 pub mod adjustments;
 #[cfg(not(target_arch = "spirv"))]
diff --git a/node-graph/gcore/src/raster/color.rs b/node-graph/gcore/src/raster/color.rs
index 7145f3dd9..f6b6d6374 100644
--- a/node-graph/gcore/src/raster/color.rs
+++ b/node-graph/gcore/src/raster/color.rs
@@ -14,6 +14,34 @@ use bytemuck::{Pod, Zeroable};
 
 use super::{Alpha, AssociatedAlpha, Luminance, Pixel, Rec709Primaries, RGB, SRGB};
 
+#[repr(C)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "std", derive(specta::Type))]
+#[derive(Debug, Default, Clone, Copy, PartialEq, DynAny, Pod, Zeroable)]
+pub struct Luma(pub f32);
+
+impl Luminance for Luma {
+	type LuminanceChannel = f32;
+	fn luminance(&self) -> f32 {
+		self.0
+	}
+}
+
+impl RGB for Luma {
+	type ColorChannel = f32;
+	fn red(&self) -> f32 {
+		self.0
+	}
+	fn green(&self) -> f32 {
+		self.0
+	}
+	fn blue(&self) -> f32 {
+		self.0
+	}
+}
+
+impl Pixel for Luma {}
+
 /// 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`,
diff --git a/node-graph/interpreted-executor/src/node_registry.rs b/node-graph/interpreted-executor/src/node_registry.rs
index 43f74ff7c..360b0d7d1 100644
--- a/node-graph/interpreted-executor/src/node_registry.rs
+++ b/node-graph/interpreted-executor/src/node_registry.rs
@@ -140,6 +140,7 @@ fn node_registry() -> HashMap<NodeIdentifier, HashMap<NodeIOTypes, NodeConstruct
 		register_node!(graphene_core::ops::SomeNode, input: ImageFrame<Color>, params: []),
 		register_node!(graphene_std::raster::DownresNode<_>, input: ImageFrame<Color>, params: []),
 		register_node!(graphene_std::raster::MaskImageNode<_, _, _>, input: ImageFrame<Color>, params: [ImageFrame<Color>]),
+		register_node!(graphene_std::raster::MaskImageNode<_, _, _>, input: ImageFrame<Color>, params: [ImageFrame<Luma>]),
 		register_node!(graphene_std::raster::EmptyImageNode<_, _>, input: DAffine2, params: [Color]),
 		#[cfg(feature = "gpu")]
 		register_node!(graphene_std::executor::MapGpuSingleImageNode<_>, input: Image<Color>, params: [String]),