switching

src/doodles/examples/circles.py

@@ -5,6 +5,6 @@ c = Circle()
 
 g = Group().pos(400, 300)
 for r in range(20, 50, 5):
-    Circle(g).radius(r).color(*Color.random()).z_index(-r)
+    Circle(g).radius(r).color(Color.random()).z_index(-r)
 for r in range(60, 150, 10):
-    Circle(g).radius(r).color(*Color.random()).z_index(-r)
+    Circle(g).radius(r).color(Color.random()).z_index(-r)

src/doodles/main.py

@@ -1,8 +1,5 @@
 import sys
-import time
-import copy
-import random
-import math
+from pathlib import Path
 import pygame
 import importlib
 import typer
@@ -11,11 +8,17 @@ from .world import world
 FPS = 60
 MS_PER_FRAME = 1000 / 60
 
-def main(modname: str):
-    pygame.init()
-    world.init()
-    pygame.display.set_caption("Doodles")
 
+def get_examples():
+    module_path = Path(__file__).parent / "examples"
+    submodules = [
+        file.stem for file in module_path.glob("*.py") if file.name != "__init__.py"
+    ]
+    return submodules
+
+def load_module(modname):
+    pygame.display.set_caption("doodles: " + modname)
+    world.clear()
     try:
         # try fully-qualified first
         mod = importlib.import_module(modname)
@@ -24,7 +27,22 @@ def main(modname: str):
         try:
             mod = importlib.import_module("doodles.examples." + modname)
         except ImportError:
-            raise ImportError(f"Tried to import {modname} and doodles.examples.{modname}")
+            raise ImportError(
+                f"Tried to import {modname} and doodles.examples.{modname}"
+            )
+    return mod
+
+
+def main(modname: str = None):
+    pygame.init()
+    world.init()
+
+    examples = get_examples()
+    ex_index = 0
+    if modname:
+        load_module(modname)
+    else:
+        load_module(examples[ex_index])
 
     elapsed = last_update = 0
 
@@ -33,6 +51,13 @@ def main(modname: str):
             if event.type == pygame.QUIT:
                 pygame.quit()
                 sys.exit()
+            elif event.type == pygame.KEYDOWN:
+                if event.key == pygame.K_RIGHT:
+                    ex_index = (ex_index + 1) % len(examples)
+                    load_module(examples[ex_index])
+                elif event.key == pygame.K_LEFT:
+                    ex_index = (ex_index - 1) % len(examples)
+                    load_module(examples[ex_index])
         elapsed = pygame.time.get_ticks() - last_update
         while elapsed > MS_PER_FRAME:
             elapsed -= MS_PER_FRAME

src/doodles/world.py

@@ -54,6 +54,9 @@ class World:
             raise ValueError("Can't initialize world twice!")
         self.screen = pygame.display.set_mode((world.WIDTH, world.HEIGHT))
 
+    def clear(self):
+        self._drawables = []
+
     def add(self, drawable):
         self._drawables.append(drawable)