Reapply "...": deduping foundation sprite seems to be buggy and does not

This reverts commit 757f443.

Author: ahyangyi

agrf/global_cache/digest.py

@@ -0,0 +1,6 @@
+import json
+import hashlib
+
+
+def digest(fingerprint):
+    return hashlib.sha384(json.dumps(fingerprint, sort_keys=True).encode()).hexdigest()

agrf/global_cache/foundation_sprite.py

@@ -0,0 +1,13 @@
+from agrf.graphics.sprites.foundation import FoundationSprite
+from .digest import digest
+
+CACHE = {}
+
+
+def make_foundation_sprite(*args, **kwargs):
+    ret = FoundationSprite(*args, **kwargs)
+    dig = digest(ret.get_fingerprint())
+
+    if dig not in CACHE:
+        CACHE[dig] = ret
+    return CACHE[dig]

agrf/global_cache/switch.py

@@ -1,8 +1,7 @@
-import json
-import hashlib
 import grf
 from agrf.magic import Switch
 from agrf.lib.building.foundation import Foundation
+from .digest import digest
 
 switch_cache = {}
 
@@ -22,7 +21,7 @@ def switch_fingerprint(s):
 
 
 def switch_hash(s):
-    return hashlib.sha384(json.dumps(switch_fingerprint(s), sort_keys=True).encode()).hexdigest()
+    return digest(switch_fingerprint(s))
 
 
 def make_switch(ranges, default, code):

agrf/lib/building/foundation.py

@@ -4,7 +4,7 @@
 from dataclasses import dataclass, replace
 from dataclass_type_validator import dataclass_type_validator
 from agrf.graphics import SCALE_TO_ZOOM
-from agrf.graphics.sprites.foundation import FoundationSprite
+from agrf.global_cache.foundation_sprite import make_foundation_sprite
 from agrf.graphics.helpers.blend import blend_alternative_sprites
 from agrf.magic import CachedFunctorMixin
 
@@ -129,7 +129,7 @@ def make_foundations_subset(self, subset):
                         g = None
 
                     if s is not None or g is not None:
-                        fs = FoundationSprite(
+                        fs = make_foundation_sprite(
                             s, g, l, r, self.cut_inside, zshift=self.zshift, zoffset=(8 if style == "ground" else 0)
                         )
                         alts.append(fs)