Add color curves layer effect

src/Classes/ShaderLoader.gd

@@ -252,6 +252,17 @@ static func create_ui_for_shader_uniforms(
 					func(_gradient, _cc): value_changed.call(gradient_edit.texture, u_name)
 				)
 				hbox.add_child(gradient_edit)
+			elif u_name.begins_with("curve_"):
+				var curve_edit := CurveEdit.new()
+				curve_edit.size_flags_horizontal = Control.SIZE_EXPAND_FILL
+				if params.has(u_name) and params[u_name] is CurveTexture:
+					curve_edit.curve = params[u_name].curve
+				else:
+					curve_edit.set_default_curve()
+				curve_edit.value_changed.connect(
+					func(curve: Curve): value_changed.call(CurveEdit.to_texture(curve), u_name)
+				)
+				hbox.add_child(curve_edit)
 			else:  ## Simple texture
 				var file_dialog := FileDialog.new()
 				file_dialog.file_mode = FileDialog.FILE_MODE_OPEN_FILE

src/UI/Nodes/CurveEditor/CurveEdit.gd

@@ -154,6 +154,12 @@ static func to_texture(from_curve: Curve, width := 256) -> CurveTexture:
 	return texture
 
 
+func set_default_curve() -> void:
+	if not is_instance_valid(curve):
+		curve = Curve.new()
+	_on_presets_item_selected(0)
+
+
 func available_size() -> Vector2:
 	if curve_editor.size.is_zero_approx():
 		return Vector2.ONE

src/UI/Timeline/LayerEffects/LayerEffectsSettings.gd

@@ -20,6 +20,7 @@ var effects: Array[LayerEffect] = [
 		"Adjust Brightness/Contrast",
 		preload("res://src/Shaders/Effects/BrightnessContrast.gdshader")
 	),
+	LayerEffect.new("Color Curves", preload("res://src/Shaders/Effects/ColorCurves.gdshader")),
 	LayerEffect.new("Palettize", preload("res://src/Shaders/Effects/Palettize.gdshader")),
 	LayerEffect.new("Pixelize", preload("res://src/Shaders/Effects/Pixelize.gdshader")),
 	LayerEffect.new("Posterize", preload("res://src/Shaders/Effects/Posterize.gdshader")),