Store shader directory as working directory and use this as the root for relative uniform image imports via !load directive, drop Windows compatibility - solves #7

src/Editor.gd

@@ -220,20 +220,26 @@ func _on_save_shader_button_pressed():
 		save_shader_dialog.current_path = last_save_filepath
 	save_shader_dialog.show()
 
-func _on_open_shader_dialog_file_selected(path):
+func _on_open_shader_dialog_file_selected(path: String):
+	print("Load ", path)
 	var file = FileAccess.open(path, FileAccess.READ)
 	var shader_code = file.get_as_text()
 	var shader = Shader.new()
 	shader.code = shader_code
 	Globals.shader = shader
+	if "/" in path: # update current working directory
+		Globals.cwd = path.substr(0, path.rfind("/"))
 	Globals.target_viewport.update()
 	update()
 	last_save_filepath = path
 
 func _on_save_shader_dialog_file_selected(path):
+	print("Save ", path)
 	var file = FileAccess.open(path, FileAccess.WRITE)
 	var content = Globals.shader.code
 	file.store_string(content)
+	if "/" in path: # update current working directory
+		Globals.cwd = path.substr(0, path.rfind("/"))
 	last_save_filepath = path
 
 func _on_apply_shader_button_pressed():

src/Globals.gd

@@ -3,3 +3,4 @@ extends Node
 var camera_freeze = false
 @onready var shader: Shader = ShaderPresets.presets[ShaderPresets.default_preset]
 var target_viewport: SubViewport
+var cwd = "."

src/ImageViewport.gd

@@ -24,7 +24,13 @@ func update():
 		# load images from //!load directives and apply them to
 		# the material as shader parameters
 		for m in load_uniform_regex.search_all(Globals.shader.code):
-			var u_image = Image.load_from_file(m.strings[2])
+			# this only works for Linux!
+			var img_path = m.strings[2]
+			if !img_path.begins_with("/"):
+				img_path = Globals.cwd + "/" + img_path.lstrip("./")
+			#
+			print("Load ", img_path)
+			var u_image = Image.load_from_file(img_path)
 			mat.set_shader_parameter(
 				m.strings[1], # uniform param name
 				ImageTexture.create_from_image(u_image))

src/Main.gd

@@ -14,6 +14,7 @@ func _on_open_image_button_pressed():
 	ui_control_fileopen.show()
 
 func _on_open_image_dialog_file_selected(path):
+	print("Load ", path)
 	var img = Image.new()
 	var err = img.load(path)
 	if err == OK:
@@ -30,6 +31,7 @@ func _on_save_image_button_pressed():
 		ui_control_filesave.show()
 
 func _on_save_image_dialog_file_selected(path):
+	print("Export ", path)
 	var err = image_viewport.get_result().save_png(path)
 	if err != OK:
 		print("An error occured!")