Cleaning up DrawArea class and moved some methods to base class

src/widgets/draw_area.py

@@ -10,34 +10,18 @@ from gi.repository import Gtk
 from gi.repository import Gdk
 
 # Application imports
-from libs.surface_manager import SurfaceManager
-from libs.event_collection import EventCollection
-
 from data.mouse_buttons import MouseButton
 from data.events import brushes
 
-from .surface import Surface
+from .draw_area_base import DrawAreaBase
 
 
 
 # Note:  https://martimm.github.io/gnome-gtk3/content-docs/tutorial/Cairo/drawing-model.html
-class DrawArea(Gtk.DrawingArea):
+class DrawArea(DrawAreaBase):
     def __init__(self):
         super(DrawArea, self).__init__()
 
-        self.background_surface: Surface       = None
-        self.primary_surface: Surface          = None
-        self.intermediate_surface: Surface     = None
-        self.surface_manager: SurfaceManager   = SurfaceManager()
-        self.event_collection: EventCollection = EventCollection()
-
-        self.is_drawing: bool                  = False
-        self.brush_mode: str                   = "Line"
-        self.grid_brush: BrushBase             = getattr(brushes, "Grid")()
-        self.brush: BrushBase                  = getattr(brushes, self.brush_mode)()
-        self.brush_color                       = self.brush.color
-        self.brush_size                        = self.brush.size
-
         self._setup_styling()
         self._setup_signals()
         self._subscribe_to_events()
@@ -47,21 +31,20 @@ class DrawArea(Gtk.DrawingArea):
  
 
     def _setup_styling(self):
-        margin_px = 24
+        super()._setup_styling()
-        self.set_margin_top(margin_px)
-        self.set_margin_left(margin_px)
-        self.set_margin_right(margin_px)
-        self.set_margin_end(margin_px)
 
     def _setup_signals(self):
         self.set_can_focus(True)
         self.set_size_request(800, 600)
 
-        self.add_events(Gdk.EventMask.KEY_PRESS_MASK)
+        self.add_events(
-        self.add_events(Gdk.EventMask.KEY_RELEASE_MASK)
+            Gdk.EventMask.KEY_PRESS_MASK      |
-        self.add_events(Gdk.EventMask.BUTTON_PRESS_MASK)
+            Gdk.EventMask.KEY_RELEASE_MASK    |
-        self.add_events(Gdk.EventMask.BUTTON_RELEASE_MASK)
+            Gdk.EventMask.BUTTON_PRESS_MASK   |
-        self.add_events(Gdk.EventMask.BUTTON1_MOTION_MASK)
+            Gdk.EventMask.BUTTON_RELEASE_MASK |
+            Gdk.EventMask.BUTTON1_MOTION_MASK |
+            Gdk.EventMask.POINTER_MOTION_MASK
+        )
 
         self.connect("key-release-event", self._key_release_event)
         self.connect("button-press-event", self._button_press_event)
@@ -79,53 +62,6 @@ class DrawArea(Gtk.DrawingArea):
     def _load_widgets(self):
         ...
 
-    def _set_new_surface(self):
-        size_w, \
-        size_h, \
-        image_surface = event_system.emit_and_await("get-image-size")
-
-        self.grid_brush.width     = size_w
-        self.grid_brush.height    = size_h
-        self.background_surface   = Surface(size_w, size_h)
-        self.primary_surface      = Surface(size_w, size_h)
-        self.intermediate_surface = Surface(size_w, size_h)
-
-        if image_surface:
-            self.primary_surface.create_new_area(image_surface)
-            self.primary_surface.set_image_data(image_surface.get_data())
-
-        self.event_collection.clear()
-        self.surface_manager.clear()
-
-        self.grid_brush.update(None)
-        self.set_size_request(size_w, size_h)
-        self.background_surface.update(self.grid_brush)
-        self.surface_manager.append( self.primary_surface )
-
-    def _save_image(self, fpath: str):
-        self.primary_surface.area.write_to_png(fpath)
-
-    def _do_save_image(self):
-        fpath = event_system.emit_and_await("save-as")
-        if not fpath: return
-        self._save_image(fpath)
-
-    def _set_brush_color(self, color: Gdk.RGBA):
-        self.brush       = getattr(brushes, self.brush_mode)()
-        self.brush_color = [color.red, color.green, color.blue, color.alpha]
-        self.brush.color = self.brush_color
-
-    def _set_brush_size(self, size: int):
-        self.brush_size  = size
-        self.brush       = getattr(brushes, self.brush_mode)()
-        self.brush.size  = self.brush_size
-
-    def _set_brush_mode(self, mode: str):
-        self.brush_mode  = mode
-        self.brush       = getattr(brushes, self.brush_mode)()
-        self.brush.color = self.brush_color
-        self.brush.size  = self.brush_size
-
     def _button_press_event(self, widget, eve):
         if not self.has_focus():
             self.grab_focus()
@@ -149,7 +85,7 @@ class DrawArea(Gtk.DrawingArea):
 
             if not self.brush.is_valid: return
     
-            self.primary_surface.update(self.brush)
+            self.active_surface.update(self.brush)
             self.queue_draw()
 
         if eve.type == Gdk.EventType.BUTTON_RELEASE and eve.button == MouseButton.RIGHT_BUTTON:
@@ -163,11 +99,11 @@ class DrawArea(Gtk.DrawingArea):
 
         if is_control:
             if keyname == "z":
-                if len(self.primary_surface.history_manager) == 0: return
+                if len(self.active_surface.history_manager) == 0: return
-                self.event_collection.append( self.primary_surface.history_manager.pop() )
+                self.event_collection.append( self.active_surface.history_manager.pop() )
             elif keyname == "y":
                 if len(self.event_collection) == 0: return
-                self.primary_surface.history_manager.append( self.event_collection.pop() )
+                self.active_surface.history_manager.append( self.event_collection.pop() )
             elif keyname == "n":
                 self._set_new_surface()
             elif keyname == "s":
@@ -175,53 +111,59 @@ class DrawArea(Gtk.DrawingArea):
 
             self.queue_draw()
 
-
     def _motion_notify_event(self, area, eve):
         if not self.is_drawing: return
         self.brush.update(eve)
         self.queue_draw()
 
+    # Note: In the future I imagine we could have different draw states
+    # besides T/F where we could call some subset order or even other surfaces
     def _draw(self, area, brush: cairo.Context):
-        self._draw_background(area, brush)
+        match self.is_drawing:
-        self._draw_surfaces(area, brush)
+            case False:
-        self._draw_overlay(area, brush)
+                self._is_not_drawing_draw_background(area, brush)
+                self._is_not_drawing_draw_surfaces(area, brush)
+                self.is_not_drawing_draw_overlay(area, brush)
+            case True:
+                self._is_drawing_draw_background(area, brush)
+                self._is_drawing_draw_surfaces(area, brush)
+                self._is_drawing_draw_overlay(area, brush)
+            case _:
+                ...
 
         return False
 
-    def _draw_background(self, area, brush: cairo.Context):
+    def _is_not_drawing_draw_background(self, area, brush: cairo.Context):
-        # Note: While drawing, only overlay needs to re-calculate its stack.
-        # This can just copy what exists than re-calculating the surface.
-        if self.is_drawing:
-            brush.set_source_surface(self.background_surface.area, 0.0, 0.0)
-            brush.paint()
-            return
-
         brush.set_source_surface(self.background_surface.area, 0.0, 0.0)
         self.background_surface.draw()
         brush.paint()
 
-    def _draw_surfaces(self, area, brush: cairo.Context):
     # Note: While drawing, only overlay needs to re-calculate its stack.
-        # This can just copy what exists than re-calculating each surface.
+    # This can just copy what exists than re-calculating the surface.
-        if self.is_drawing:
+    def _is_drawing_draw_background(self, area, brush: cairo.Context):
-            for surface in self.surface_manager:
+        brush.set_source_surface(self.background_surface.area, 0.0, 0.0)
-                brush.set_source_surface(surface.area, 0.0, 0.0)
-
         brush.paint()
-            return
 
+    def _is_not_drawing_draw_surfaces(self, area, brush: cairo.Context):
         for surface in self.surface_manager:
             brush.set_source_surface(surface.area, 0.0, 0.0)
             surface.draw()
 
         brush.paint()
 
-    def _draw_overlay(self, area, brush: cairo.Context):
+    # Note: While drawing, only overlay needs to re-calculate its stack.
-        # Note: When NOT drawing, no overlay data should exist nor be processed...
+    # This can just copy what exists than re-calculating each surface.
-        if not self.is_drawing:
+    def _is_drawing_draw_surfaces(self, area, brush: cairo.Context):
-            self.intermediate_surface.clear_surface()
+        for surface in self.surface_manager:
-            return
+            brush.set_source_surface(surface.area, 0.0, 0.0)
 
+        brush.paint()
+
+    # Note: When NOT drawing, no overlay data should exist nor be processed...
+    def is_not_drawing_draw_overlay(self, area, brush: cairo.Context):
+        self.intermediate_surface.clear_surface()
+
+    def _is_drawing_draw_overlay(self, area, brush: cairo.Context):
         brush.set_source_surface(self.intermediate_surface.area, 0.0, 0.0)
         self.intermediate_surface.draw()
         brush.paint()

src/widgets/draw_area_base.py

@@ -0,0 +1,93 @@
+# Python imports
+
+# Lib imports
+import gi
+gi.require_version('Gtk', '3.0')
+
+from gi.repository import Gtk
+from gi.repository import Gdk
+
+# Application imports
+from libs.surface_manager import SurfaceManager
+from libs.event_collection import EventCollection
+
+from data.mouse_buttons import MouseButton
+from data.events import brushes
+
+from .surface import Surface
+
+
+
+# Note:  https://martimm.github.io/gnome-gtk3/content-docs/tutorial/Cairo/drawing-model.html
+class DrawAreaBase(Gtk.DrawingArea):
+    def __init__(self):
+        super(DrawAreaBase, self).__init__()
+
+        self.background_surface: Surface       = None
+        self.active_surface: Surface           = None
+        self.intermediate_surface: Surface     = None
+        self.surface_manager: SurfaceManager   = SurfaceManager()
+        self.event_collection: EventCollection = EventCollection()
+
+        self.is_drawing: bool                  = False
+        self.brush_mode: str                   = "Line"
+        self.grid_brush: BrushBase             = getattr(brushes, "Grid")()
+        self.brush: BrushBase                  = getattr(brushes, self.brush_mode)()
+        self.brush_color                       = self.brush.color
+        self.brush_size                        = self.brush.size
+
+
+    def _setup_styling(self):
+        margin_px = 24
+        self.set_margin_top(margin_px)
+        self.set_margin_left(margin_px)
+        self.set_margin_right(margin_px)
+        self.set_margin_end(margin_px)
+
+    def _set_new_surface(self):
+        size_w, \
+        size_h, \
+        image_surface = event_system.emit_and_await("get-image-size")
+
+        self.grid_brush.width     = size_w
+        self.grid_brush.height    = size_h
+        self.background_surface   = Surface(size_w, size_h)
+        self.active_surface       = Surface(size_w, size_h)
+        self.intermediate_surface = Surface(size_w, size_h)
+
+        if image_surface:
+            self.active_surface.create_new_area(image_surface)
+            self.active_surface.set_image_data(image_surface.get_data())
+
+        self.event_collection.clear()
+        self.surface_manager.clear()
+
+        self.grid_brush.update(None)
+        self.set_size_request(size_w, size_h)
+        self.background_surface.update(self.grid_brush)
+        self.surface_manager.append( self.active_surface )
+
+    def _save_image(self, fpath: str):
+        self.active_surface.area.write_to_png(fpath)
+
+    def _do_save_image(self):
+        fpath = event_system.emit_and_await("save-as")
+        if not fpath: return
+        self._save_image(fpath)
+
+    def _set_brush_color(self, color: Gdk.RGBA):
+        self.brush       = getattr(brushes, self.brush_mode)()
+        self.brush_color = [color.red, color.green, color.blue, color.alpha]
+        self.brush.color = self.brush_color
+
+    def _set_brush_size(self, size: int):
+        self.brush_size  = size
+        self.brush       = getattr(brushes, self.brush_mode)()
+        self.brush.size  = self.brush_size
+
+    def _set_brush_mode(self, mode: str):
+        self.brush_mode  = mode
+        self.brush       = getattr(brushes, self.brush_mode)()
+        self.brush.color = self.brush_color
+        self.brush.size  = self.brush_size
+