Prep gcore splitup: move various symbols into their own modules (#2746)

* move `trait AsU32` from `gcore::vector::misc` to `gcore`

* move blending and gradient to their own modules

* fix unused warnings

* move `Quad`, `Rect` and `BBox` to `gcore::math`

* extract `ReferencePoint` and transform nodes from `transform`

* move color-related code to `mod color`

* fix unused warning in test code

* move blending-related nodes and code to `mod blending_nodes`

* move ClickTarget code to `mod vector::click_target`

node-graph/gcore/src/blending_nodes.rs

@@ -0,0 +1,175 @@
+use crate::raster::Image;
+use crate::raster_types::{CPU, RasterDataTable};
+use crate::registry::types::Percentage;
+use crate::vector::VectorDataTable;
+use crate::{BlendMode, Color, Ctx, GraphicElement, GraphicGroupTable};
+
+pub(super) trait MultiplyAlpha {
+	fn multiply_alpha(&mut self, factor: f64);
+}
+
+impl MultiplyAlpha for Color {
+	fn multiply_alpha(&mut self, factor: f64) {
+		*self = Color::from_rgbaf32_unchecked(self.r(), self.g(), self.b(), (self.a() * factor as f32).clamp(0., 1.))
+	}
+}
+impl MultiplyAlpha for VectorDataTable {
+	fn multiply_alpha(&mut self, factor: f64) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.opacity *= factor as f32;
+		}
+	}
+}
+impl MultiplyAlpha for GraphicGroupTable {
+	fn multiply_alpha(&mut self, factor: f64) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.opacity *= factor as f32;
+		}
+	}
+}
+impl MultiplyAlpha for RasterDataTable<CPU>
+where
+	GraphicElement: From<Image<Color>>,
+{
+	fn multiply_alpha(&mut self, factor: f64) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.opacity *= factor as f32;
+		}
+	}
+}
+
+pub(super) trait MultiplyFill {
+	fn multiply_fill(&mut self, factor: f64);
+}
+impl MultiplyFill for Color {
+	fn multiply_fill(&mut self, factor: f64) {
+		*self = Color::from_rgbaf32_unchecked(self.r(), self.g(), self.b(), (self.a() * factor as f32).clamp(0., 1.))
+	}
+}
+impl MultiplyFill for VectorDataTable {
+	fn multiply_fill(&mut self, factor: f64) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.fill *= factor as f32;
+		}
+	}
+}
+impl MultiplyFill for GraphicGroupTable {
+	fn multiply_fill(&mut self, factor: f64) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.fill *= factor as f32;
+		}
+	}
+}
+impl MultiplyFill for RasterDataTable<CPU> {
+	fn multiply_fill(&mut self, factor: f64) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.fill *= factor as f32;
+		}
+	}
+}
+
+trait SetBlendMode {
+	fn set_blend_mode(&mut self, blend_mode: BlendMode);
+}
+
+impl SetBlendMode for VectorDataTable {
+	fn set_blend_mode(&mut self, blend_mode: BlendMode) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.blend_mode = blend_mode;
+		}
+	}
+}
+impl SetBlendMode for GraphicGroupTable {
+	fn set_blend_mode(&mut self, blend_mode: BlendMode) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.blend_mode = blend_mode;
+		}
+	}
+}
+impl SetBlendMode for RasterDataTable<CPU> {
+	fn set_blend_mode(&mut self, blend_mode: BlendMode) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.blend_mode = blend_mode;
+		}
+	}
+}
+
+trait SetClip {
+	fn set_clip(&mut self, clip: bool);
+}
+
+impl SetClip for VectorDataTable {
+	fn set_clip(&mut self, clip: bool) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.clip = clip;
+		}
+	}
+}
+impl SetClip for GraphicGroupTable {
+	fn set_clip(&mut self, clip: bool) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.clip = clip;
+		}
+	}
+}
+impl SetClip for RasterDataTable<CPU> {
+	fn set_clip(&mut self, clip: bool) {
+		for instance in self.instance_mut_iter() {
+			instance.alpha_blending.clip = clip;
+		}
+	}
+}
+
+#[node_macro::node(category("Style"))]
+fn blend_mode<T: SetBlendMode>(
+	_: impl Ctx,
+	#[implementations(
+		GraphicGroupTable,
+		VectorDataTable,
+		RasterDataTable<CPU>,
+	)]
+	mut value: T,
+	blend_mode: BlendMode,
+) -> T {
+	// TODO: Find a way to make this apply once to the table's parent (i.e. its row in its parent table or Instance<T>) rather than applying to each row in its own table, which produces the undesired result
+	value.set_blend_mode(blend_mode);
+	value
+}
+
+#[node_macro::node(category("Style"))]
+fn opacity<T: MultiplyAlpha>(
+	_: impl Ctx,
+	#[implementations(
+		GraphicGroupTable,
+		VectorDataTable,
+		RasterDataTable<CPU>,
+	)]
+	mut value: T,
+	#[default(100.)] opacity: Percentage,
+) -> T {
+	// TODO: Find a way to make this apply once to the table's parent (i.e. its row in its parent table or Instance<T>) rather than applying to each row in its own table, which produces the undesired result
+	value.multiply_alpha(opacity / 100.);
+	value
+}
+
+#[node_macro::node(category("Style"))]
+fn blending<T: SetBlendMode + MultiplyAlpha + MultiplyFill + SetClip>(
+	_: impl Ctx,
+	#[implementations(
+		GraphicGroupTable,
+		VectorDataTable,
+		RasterDataTable<CPU>,
+	)]
+	mut value: T,
+	blend_mode: BlendMode,
+	#[default(100.)] opacity: Percentage,
+	#[default(100.)] fill: Percentage,
+	#[default(false)] clip: bool,
+) -> T {
+	// TODO: Find a way to make this apply once to the table's parent (i.e. its row in its parent table or Instance<T>) rather than applying to each row in its own table, which produces the undesired result
+	value.set_blend_mode(blend_mode);
+	value.multiply_alpha(opacity / 100.);
+	value.multiply_fill(fill / 100.);
+	value.set_clip(clip);
+	value
+}