most things working, not text, draw_engine interface still fluid

src/doodles/doodles.py

@@ -46,7 +46,7 @@ class Doodle(ABC):
         world.add(self)
 
     @abstractmethod
-    def draw(self, screen) -> None:
+    def draw(self) -> None:
         """
         All doodles need to be drawable, but there is no
         way we can provide an implementation without
@@ -231,7 +231,7 @@ class Group(Doodle):
     def __repr__(self):
         return f"Group(pos={self.world_vec}, doodles={len(self._doodles)})"
 
-    def draw(self, screen):
+    def draw(self):
         """
         Groups, despite being an abstract concept, are drawable.
         To draw a group is to draw everything in it.

src/doodles/draw_engine.py

@@ -0,0 +1,17 @@
+import abc
+
+
+class DrawEngine(abc.ABC):
+    @abc.abstractmethod
+    def circle_draw(self, screen):
+        pass
+
+    @abc.abstractmethod
+    def rect_draw(self, screen):
+        pass
+
+    @abc.abstractmethod
+    def line_draw(self, screen):
+        pass
+
+

src/doodles/lines.py

@@ -3,6 +3,7 @@ import random
 import pygame
 from typing import Callable
 from .doodles import Doodle
+from .world import world
 
 
 class Line(Doodle):
@@ -22,7 +23,7 @@ class Line(Doodle):
     def __repr__(self):
         return f"Line(pos={self.world_vec}, end={self.end_vec}, {self._color})"
 
-    def draw(self, screen):
+    def draw(self):
         """
         Implementation of the abstract draw function for the line.
 
@@ -41,7 +42,7 @@ class Line(Doodle):
         to the class and gaining flexibility from separating
         presentation logic from data manipulation.
         """
-        pygame.draw.aaline(screen, self._color, self.world_vec, self.end_vec)
+        world.draw_engine.line_draw(self)
 
     def to(self, x: float, y: float) -> "Doodle":
         """

src/doodles/shapes.py

@@ -1,6 +1,7 @@
 import random
 import pygame
 from .doodles import Doodle
+from .world import world
 
 
 class Circle(Doodle):
@@ -15,8 +16,9 @@ class Circle(Doodle):
     def __repr__(self):
         return f"Circle(pos={self.world_vec}, radius={self._radius}, {self._color}, parent={self._parent}))"
 
-    def draw(self, screen):
+    def draw(self):
-        pygame.draw.circle(screen, self.rgba, self.world_vec, self._radius)
+        # TODO: do we need to override draw? can we move this to Doodle.draw
+        world.draw_engine.circle_draw(self)
 
     def radius(self, r: float) -> "Doodle":
         """
@@ -25,6 +27,10 @@ class Circle(Doodle):
         self._radius = r
         return self
 
+    @property
+    def radius_val(self) -> float:
+        return self._radius
+
     def grow(self, by: float):
         """
         Modify radius by an amount. (Negative to shrink.)
@@ -50,14 +56,8 @@ class Rectangle(Doodle):
     def __repr__(self):
         return f"Rect(pos={self.world_vec}, width={self._width}, height={self._height}, parent={self._parent})"
 
-    def draw(self, screen):
+    def draw(self):
-        rect = pygame.Rect(
+        world.draw_engine.rect_draw(self)
-            self.world_x - self._width / 2,
-            self.world_y - self._height / 2,
-            self._width,
-            self._height,
-        )
-        pygame.draw.rect(screen, self._color, rect)
 
     def width(self, w: float) -> "Doodle":
         """

src/doodles/world.py

@@ -1,5 +1,26 @@
 from .color import Color
 import pygame
+# TODO: fix this with a dynamic load
+from .draw_engine import DrawEngine
+
+
+class PygameDrawEngine(DrawEngine):
+    def circle_draw(self, c: "Circle"):
+        pygame.draw.circle(world.buffer, c.rgba, c.world_vec, c.radius_val)
+
+    def rect_draw(self, r: "Rectangle"):
+        # TODO: make accessors
+        rect = pygame.Rect(
+            r.world_x - r._width / 2,
+            r.world_y - r._height / 2,
+            r._width,
+            r._height,
+        )
+        pygame.draw.rect(world.buffer, r.rgba, rect)
+
+    def line_draw(self, ll: "Line"):
+        print("line_draw", ll)
+        pygame.draw.aaline(world.buffer, ll.rgba, ll.world_vec, ll.end_vec)
 
 
 class World:
@@ -48,6 +69,7 @@ class World:
         self._drawables = []
         self.background_color = Color.WHITE
         self.screen = None
+        self.draw_engine = PygameDrawEngine()
 
     def init(self):
         """
@@ -85,7 +107,7 @@ class World:
         # rendering
         self.buffer.fill((*self.background_color, 255))
         for d in sorted(self._drawables, key=lambda d: d._z_index):
-            d.draw(self.buffer)
+            d.draw()
         self.screen.blit(self.buffer, (0, 0))
         pygame.display.flip()