Implement Reference Image Support

src/ui_parts/display.gd

@@ -17,15 +17,19 @@ const NumberField = preload("res://src/ui_elements/number_field.tscn")
 @onready var viewport: SubViewport = $ViewportPanel/ViewportContainer/Viewport
 @onready var controls: Control = %Checkerboard/Controls
 @onready var grid_visuals: Control = %Camera
+@onready var reference_texture : TextureRect = %ReferenceTexture
 @onready var visuals_button: Button = %LeftMenu/Visuals
 @onready var more_button: Button = %LeftMenu/MoreOptions
+@onready var reference_button : Button = %LeftMenu/Reference
 @onready var snapper: NumberEditType = %LeftMenu/Snapping/SnapNumberEdit
 @onready var snap_button: BetterToggleButtonType = %LeftMenu/Snapping/SnapButton
 @onready var panel_container: PanelContainer = $PanelContainer
 @onready var viewport_panel: PanelContainer = $ViewportPanel
 
+var reference_overlay = false
 
 func _ready() -> void:
+	reference_texture.hide()
 	update_snap_config()
 	view_settings_updated.emit(grid_visuals.visible, controls.visible,
 			viewport.display_texture.rasterized)
@@ -99,6 +103,18 @@ func _on_visuals_button_pressed() -> void:
 	HandlerGUI.popup_under_rect_center(visuals_popup, visuals_button.get_global_rect(),
 			get_viewport())
 
+func _on_reference_pressed() -> void:
+	var btn_arr: Array[Button] = [
+		Utils.create_btn(tr("Select Image"), open_reference_file, false, load("res://visual/icons/Reference.svg")),
+		Utils.create_checkbox(tr("Show Reference Image"), toggle_reference_visuals, reference_texture.visible),
+		Utils.create_checkbox(tr("Overlay Reference Image"), toggle_reference_overlay, reference_overlay)
+	]
+
+	var reference_popup := ContextPopup.new()
+	reference_popup.setup(btn_arr, true)
+	HandlerGUI.popup_under_rect_center(reference_popup, reference_button.get_global_rect(), get_viewport())
+
+
 func _on_more_options_pressed() -> void:
 	var about_btn := Utils.create_btn(tr("About…"), open_about, false,
 			load("res://visual/icon.svg"))
@@ -139,6 +155,20 @@ func open_update_checker() -> void:
 	var update_menu_instance := update_menu.instantiate()
 	HandlerGUI.add_overlay(update_menu_instance)
 
+func open_reference_file() -> void:
+	# TODO: Add web and GoodFileDialog support.
+	DisplayServer.file_dialog_show("Import a .png file", Utils.get_last_dir(), "", false,
+		DisplayServer.FILE_DIALOG_MODE_OPEN_FILE, ["*.png"], native_reference_import)
+
+func toggle_reference_overlay() -> void:
+	reference_overlay = not reference_overlay
+	if reference_overlay: 
+		viewport.move_child(reference_texture, 2)
+	else:
+		viewport.move_child(reference_texture, 0)
+
+func toggle_reference_visuals() -> void:
+	reference_texture.visible = not reference_texture.visible
 
 func toggle_grid_visuals() -> void:
 	grid_visuals.visible = not grid_visuals.visible
@@ -163,6 +193,12 @@ func set_snap_amount(snap_value: float) -> void:
 	snapper.set_value(snap_value)
 
 
+func native_reference_import(has_selected: bool, files: PackedStringArray, _filter_idx: int) -> void:
+	if has_selected:
+		if files[0].ends_with(".png"):
+			reference_texture.texture = load(files[0])
+			reference_texture.visible = true
+
 func _on_snap_button_toggled(toggled_on: bool) -> void:
 	GlobalSettings.modify_save_data("snap",
 			absf(GlobalSettings.save_data.snap) * (1 if toggled_on else -1))

src/ui_parts/display.tscn

@@ -1,10 +1,11 @@
-[gd_scene load_steps=17 format=3 uid="uid://bvrncl7e6yn5b"]
+[gd_scene load_steps=18 format=3 uid="uid://bvrncl7e6yn5b"]
 
 [ext_resource type="Script" path="res://src/ui_parts/display.gd" id="1_oib5g"]
 [ext_resource type="Texture2D" uid="uid://ccbta5q43jobk" path="res://visual/icons/More.svg" id="2_3wliq"]
 [ext_resource type="Texture2D" uid="uid://ckkkgof1hcbld" path="res://visual/icons/Gear.svg" id="3_0w618"]
 [ext_resource type="Texture2D" uid="uid://kkxyv1gyrjgj" path="res://visual/icons/Visuals.svg" id="4_n3qjt"]
 [ext_resource type="Texture2D" uid="uid://buire51l0mifg" path="res://visual/icons/Snap.svg" id="5_1k2cq"]
+[ext_resource type="Texture2D" uid="uid://bvoetuaifdv8i" path="res://visual/icons/Reference.svg" id="5_qufah"]
 [ext_resource type="Script" path="res://src/ui_elements/BetterToggleButton.gd" id="6_3v3ve"]
 [ext_resource type="PackedScene" uid="uid://dad7fkhmsooc6" path="res://src/ui_elements/number_edit.tscn" id="7_wrrfr"]
 [ext_resource type="PackedScene" uid="uid://oltvrf01xrxl" path="res://src/ui_parts/zoom_menu.tscn" id="8_xtdmn"]
@@ -66,6 +67,16 @@ theme_type_variation = &"IconButton"
 icon = ExtResource("3_0w618")
 icon_alignment = 1
 
+[node name="Reference" type="Button" parent="PanelContainer/HBoxContainer/LeftMenu"]
+layout_mode = 2
+size_flags_horizontal = 2
+tooltip_text = "Visuals"
+focus_mode = 0
+mouse_default_cursor_shape = 2
+theme_type_variation = &"IconButton"
+icon = ExtResource("5_qufah")
+icon_alignment = 1
+
 [node name="Visuals" type="Button" parent="PanelContainer/HBoxContainer/LeftMenu"]
 layout_mode = 2
 size_flags_horizontal = 2
@@ -125,6 +136,13 @@ size_2d_override_stretch = true
 render_target_update_mode = 4
 script = ExtResource("9_4xrk7")
 
+[node name="ReferenceTexture" type="TextureRect" parent="ViewportPanel/ViewportContainer/Viewport"]
+unique_name_in_owner = true
+offset_right = 40.0
+offset_bottom = 40.0
+expand_mode = 1
+stretch_mode = 5
+
 [node name="Checkerboard" type="TextureRect" parent="ViewportPanel/ViewportContainer/Viewport"]
 unique_name_in_owner = true
 texture_filter = 1
@@ -163,6 +181,7 @@ script = ExtResource("15_hevpa")
 
 [connection signal="pressed" from="PanelContainer/HBoxContainer/LeftMenu/MoreOptions" to="." method="_on_more_options_pressed"]
 [connection signal="pressed" from="PanelContainer/HBoxContainer/LeftMenu/Settings" to="." method="_on_settings_pressed"]
+[connection signal="pressed" from="PanelContainer/HBoxContainer/LeftMenu/Reference" to="." method="_on_reference_pressed"]
 [connection signal="pressed" from="PanelContainer/HBoxContainer/LeftMenu/Visuals" to="." method="_on_visuals_button_pressed"]
 [connection signal="toggled" from="PanelContainer/HBoxContainer/LeftMenu/Snapping/SnapButton" to="." method="_on_snap_button_toggled"]
 [connection signal="value_changed" from="PanelContainer/HBoxContainer/LeftMenu/Snapping/SnapNumberEdit" to="." method="_on_snap_number_edit_value_changed"]

src/ui_parts/viewport.gd

@@ -12,6 +12,7 @@ var _zoom_to: Vector2
 @onready var view: Control = %Camera
 @onready var controls: Control = %Checkerboard/Controls
 @onready var display_texture: TextureRect = %Checkerboard/DisplayTexture
+@onready var reference_texture : TextureRect = $ReferenceTexture
 @onready var zoom_menu: ZoomMenuType = %ZoomMenu
 
 
@@ -42,6 +43,7 @@ func set_view(new_position: Vector2) -> void:
 func resize() -> void:
 	if SVG.root_tag.get_size().is_finite():
 		display.size = SVG.root_tag.get_size()
+		reference_texture.size = SVG.root_tag.get_size()
 	zoom_menu.zoom_reset()
 
 func center_frame() -> void:

visual/icons/Reference.svg.import

@@ -0,0 +1,37 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://bvoetuaifdv8i"
+path="res://.godot/imported/Reference.svg-28e3f2638dc2f67db7899c414706e462.ctex"
+metadata={
+"vram_texture": false
+}
+
+[deps]
+
+source_file="res://visual/icons/Reference.svg"
+dest_files=["res://.godot/imported/Reference.svg-28e3f2638dc2f67db7899c414706e462.ctex"]
+
+[params]
+
+compress/mode=0
+compress/high_quality=false
+compress/lossy_quality=0.7
+compress/hdr_compression=1
+compress/normal_map=0
+compress/channel_pack=0
+mipmaps/generate=false
+mipmaps/limit=-1
+roughness/mode=0
+roughness/src_normal=""
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/normal_map_invert_y=false
+process/hdr_as_srgb=false
+process/hdr_clamp_exposure=false
+process/size_limit=0
+detect_3d/compress_to=1
+svg/scale=1.0
+editor/scale_with_editor_scale=false
+editor/convert_colors_with_editor_theme=false