Initial commit

game/assets.py

@@ -0,0 +1,72 @@
+"""Sprite loading with graceful placeholders.
+
+Every drawable in the game asks the AssetStore for a surface by name. If a PNG
+named ``<name>.png`` exists in the assets directory it is loaded and scaled to
+the requested size; otherwise a labeled colored rectangle is drawn instead, so
+the game is fully playable before any art exists.
+"""
+
+import os
+import pygame
+
+from . import settings
+
+
+class AssetStore:
+    def __init__(self, assets_dir):
+        self.assets_dir = assets_dir
+        self._raw = {}       # name -> original loaded Surface (or None if missing)
+        self._cache = {}     # (name, w, h) -> scaled Surface
+        self._font = None
+
+    def _font_for(self, h):
+        # Lazily build a font sized to the tile so placeholder labels fit.
+        size = max(10, int(h * 0.5))
+        return pygame.font.SysFont("consolas,menlo,monospace", size, bold=True)
+
+    def _load_raw(self, name):
+        if name in self._raw:
+            return self._raw[name]
+        path = os.path.join(self.assets_dir, name + ".png")
+        surf = None
+        if os.path.isfile(path):
+            try:
+                surf = pygame.image.load(path).convert_alpha()
+            except pygame.error:
+                surf = None
+        self._raw[name] = surf
+        return surf
+
+    def get(self, name, w, h, angle=0):
+        """Return a Surface of exactly (w, h) for the given sprite name,
+        optionally rotated counter-clockwise by ``angle`` degrees first (used to
+        point directional sprites like spikes the right way)."""
+        w, h = int(w), int(h)
+        angle %= 360
+        key = (name, w, h, angle)
+        if key in self._cache:
+            return self._cache[key]
+
+        raw = self._load_raw(name)
+        if raw is not None:
+            if angle:
+                raw = pygame.transform.rotate(raw, angle)
+            # Nearest-neighbour keeps the pixel-art sprites crisp at any size.
+            surf = pygame.transform.scale(raw, (w, h))
+        else:
+            surf = self._make_placeholder(name, w, h)
+
+        self._cache[key] = surf
+        return surf
+
+    def _make_placeholder(self, name, w, h):
+        color, label = settings.PLACEHOLDERS.get(name, ((200, 60, 200), "?"))
+        surf = pygame.Surface((w, h), pygame.SRCALPHA)
+        surf.fill(color)
+        # A subtle border helps distinguish adjacent tiles of the same color.
+        pygame.draw.rect(surf, (0, 0, 0, 90), surf.get_rect(), max(1, w // 16))
+        if label:
+            font = self._font_for(h)
+            text = font.render(label, True, (15, 15, 20))
+            surf.blit(text, text.get_rect(center=(w // 2, h // 2)))
+        return surf