Implement shrink option (#376)

* Add shrink option that allow change default shrink

Shrink option allow to scale the godot application. This path enable
dynamic change of this value in the options.

* Fix the computation of cursor location

For an unknown reason the function get_local_mouse_position return
incorrect current_pixel when shrink is not 1. This path compute the
transformation manually and povide correct values for any shrink value.

src/Autoload/Global.gd

@@ -45,6 +45,7 @@ var default_clear_color := Color.gray
 # Preferences
 var pressure_sensitivity_mode = Pressure_Sensitivity.NONE
 var open_last_project := false
+var shrink := 1.0
 var smooth_zoom := true
 var theme_type : int = Theme_Types.DARK
 var default_image_width := 64

src/Main.gd

@@ -67,6 +67,9 @@ func setup_application_window_size() -> void:
 	# Set a minimum window size to prevent UI elements from collapsing on each other.
 	OS.min_window_size = Vector2(1024, 576)
 	
+	get_tree().set_screen_stretch(SceneTree.STRETCH_MODE_DISABLED,
+		SceneTree.STRETCH_ASPECT_IGNORE, Vector2(1014,576), Global.shrink)
+
 	# Restore the window position/size if values are present in the configuration cache
 	if Global.config_cache.has_section_key("window", "screen"):
 		OS.current_screen = Global.config_cache.get_value("window", "screen")

src/Preferences/PreferencesDialog.gd

@@ -3,6 +3,7 @@ extends AcceptDialog
 # Preferences table: [Prop name in Global, relative node path, value type, default value]
 var preferences = [
 	["open_last_project", "Startup/StartupContainer/OpenLastProject", "pressed", Global.open_last_project],
+	["shrink", "Startup/ShrinkContainer/ShrinkHSlider", "value", Global.shrink],
 	["smooth_zoom", "Canvas/ZoomOptions/SmoothZoom", "pressed", Global.smooth_zoom],
 	["pressure_sensitivity_mode", "Startup/PressureSentivity/PressureSensitivityOptionButton", "selected", Global.pressure_sensitivity_mode],
 	["show_left_tool_icon", "Indicators/IndicatorsContainer/LeftToolIconCheckbox", "pressed", Global.show_left_tool_icon],
@@ -36,6 +37,7 @@ onready var list : ItemList = $HSplitContainer/List
 onready var right_side : VBoxContainer = $HSplitContainer/ScrollContainer/VBoxContainer
 onready var autosave_interval : SpinBox = $HSplitContainer/ScrollContainer/VBoxContainer/Backup/AutosaveContainer/AutosaveInterval
 onready var restore_default_button_scene = preload("res://src/Preferences/RestoreDefaultButton.tscn")
+onready var shrink_label : Label = $HSplitContainer/ScrollContainer/VBoxContainer/Startup/ShrinkContainer/ShrinkLabel
 
 
 func _ready() -> void:
@@ -172,3 +174,15 @@ func _on_List_item_selected(index : int) -> void:
 		if OS.get_name() == "HTML5":
 			content_list.erase("Startup")
 		child.visible = child.name == content_list[index]
+
+
+func _on_HSlider_value_changed(value):
+	shrink_label.text = str(value)
+
+
+func _on_ShrinkApplyButton_pressed():
+	get_tree().set_screen_stretch(SceneTree.STRETCH_MODE_DISABLED,
+		SceneTree.STRETCH_ASPECT_IGNORE, Vector2(1014,576), Global.shrink)
+	Global.preferences_dialog.popup_centered(Vector2(400, 280))
+	Global.camera.zoom_100()
+	

src/Preferences/PreferencesDialog.tscn

@@ -8,6 +8,7 @@
 [sub_resource type="ButtonGroup" id=1]
 
 [node name="PreferencesDialog" type="AcceptDialog"]
+visible = true
 margin_left = -3.0
 margin_top = 9.0
 margin_right = 419.0
@@ -51,12 +52,12 @@ size_flags_horizontal = 3
 
 [node name="VBoxContainer" type="VBoxContainer" parent="HSplitContainer/ScrollContainer"]
 margin_right = 498.0
-margin_bottom = 24.0
+margin_bottom = 48.0
 size_flags_horizontal = 3
 
 [node name="Startup" type="VBoxContainer" parent="HSplitContainer/ScrollContainer/VBoxContainer"]
 margin_right = 498.0
-margin_bottom = 24.0
+margin_bottom = 48.0
 
 [node name="StartupContainer" type="HBoxContainer" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup"]
 margin_right = 498.0
@@ -78,9 +79,9 @@ text = "On"
 
 [node name="PressureSentivity" type="HBoxContainer" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup"]
 visible = false
-margin_top = 100.0
-margin_right = 506.0
-margin_bottom = 120.0
+margin_top = 28.0
+margin_right = 498.0
+margin_bottom = 48.0
 
 [node name="PressureSensitivityLabel" type="Label" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup/PressureSentivity"]
 margin_top = 3.0
@@ -96,6 +97,44 @@ text = "Affect Brush's Alpha"
 items = [ "None", null, false, 0, null, "Affect Brush's Alpha", null, false, 1, null ]
 selected = 1
 
+[node name="ShrinkContainer" type="HBoxContainer" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup"]
+margin_top = 28.0
+margin_right = 498.0
+margin_bottom = 48.0
+
+[node name="Label" type="Label" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup/ShrinkContainer"]
+margin_top = 3.0
+margin_right = 68.0
+margin_bottom = 17.0
+text = "Shrink GUI"
+
+[node name="ShrinkLabel" type="Label" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup/ShrinkContainer"]
+margin_left = 72.0
+margin_top = 3.0
+margin_right = 122.0
+margin_bottom = 17.0
+rect_min_size = Vector2( 50, 0 )
+text = "1"
+align = 2
+
+[node name="ShrinkHSlider" type="HSlider" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup/ShrinkContainer"]
+margin_left = 126.0
+margin_right = 446.0
+margin_bottom = 16.0
+size_flags_horizontal = 3
+min_value = 1.0
+max_value = 4.0
+step = 0.5
+value = 1.0
+tick_count = 7
+ticks_on_borders = true
+
+[node name="ShrinkApplyButton" type="Button" parent="HSplitContainer/ScrollContainer/VBoxContainer/Startup/ShrinkContainer"]
+margin_left = 450.0
+margin_right = 498.0
+margin_bottom = 20.0
+text = "Apply"
+
 [node name="Languages" type="VBoxContainer" parent="HSplitContainer/ScrollContainer/VBoxContainer"]
 visible = false
 margin_top = 184.0
@@ -939,6 +978,8 @@ __meta__ = {
 [connection signal="about_to_show" from="." to="." method="_on_PreferencesDialog_about_to_show"]
 [connection signal="popup_hide" from="." to="." method="_on_PreferencesDialog_popup_hide"]
 [connection signal="item_selected" from="HSplitContainer/List" to="." method="_on_List_item_selected"]
+[connection signal="value_changed" from="HSplitContainer/ScrollContainer/VBoxContainer/Startup/ShrinkContainer/ShrinkHSlider" to="." method="_on_HSlider_value_changed"]
+[connection signal="pressed" from="HSplitContainer/ScrollContainer/VBoxContainer/Startup/ShrinkContainer/ShrinkApplyButton" to="." method="_on_ShrinkApplyButton_pressed"]
 [connection signal="item_selected" from="HSplitContainer/ScrollContainer/VBoxContainer/Shortcuts/HBoxContainer/PresetOptionButton" to="HSplitContainer/ScrollContainer/VBoxContainer/Shortcuts" method="_on_PresetOptionButton_item_selected"]
 [connection signal="confirmed" from="Popups/ShortcutSelector" to="HSplitContainer/ScrollContainer/VBoxContainer/Shortcuts" method="_on_ShortcutSelector_confirmed"]
 [connection signal="popup_hide" from="Popups/ShortcutSelector" to="HSplitContainer/ScrollContainer/VBoxContainer/Shortcuts" method="_on_ShortcutSelector_popup_hide"]

src/UI/Canvas/Canvas.gd

@@ -50,7 +50,10 @@ func _input(event : InputEvent) -> void:
 #	elif not get_viewport_rect().has_point(event.position):
 #		return
 
-	current_pixel = get_local_mouse_position() + location
+	#current_pixel = get_local_mouse_position() + location
+	var tmp_transform = get_canvas_transform().affine_inverse()
+	var tmp_position = Global.main_viewport.get_local_mouse_position()
+	current_pixel = tmp_transform.basis_xform(tmp_position)+tmp_transform.origin
 
 	if Global.has_focus:
 		update()