Add ability to write on map

Todo:
 - make ChunkDiffs contain deletions
 - inserting a " " counts as deletion on chunk level
 - allow for more unicode characters! ^^ (only harmless ones though - no newline or control characters etc.)

chunks.py

@@ -1,12 +1,59 @@
 import threading
+import time
+from utils import CHUNK_WIDTH, CHUNK_HEIGHT
 
 class ChunkDiff():
 	"""
 	Represents differences between two chunks (changes to be made to a chunk).
 	Can be used to transform a chunk into another chunk.
+	
+	Todo: Implement delete diff
 	"""
 	
-	pass
+	@classmethod
+	def combine(cls, diff_a, diff_b):
+		diff = cls()
+		diff.apply(diff_a)
+		diff.apply(diff_b)
+		return diff
+	
+	def __init__(self):
+		self._chars = {}
+	
+	@classmethod
+	def from_dict(cls, d):
+		diff = cls()
+		diff._chars = d
+		return diff
+		#self._chars = d.copy()
+	
+	def copy(self):
+		return ChunkDiff.from_dict(self.to_dict().copy())
+	
+	def combine(self, diff):
+		newdiff = self.copy()
+		newdiff.apply(diff)
+		return newdiff
+	
+	def to_dict(self):
+		return self._chars
+		#return self._chars.copy()
+	
+	def set(self, x, y, character):
+		self._chars[x+y*CHUNK_WIDTH] = character
+	
+	def delete(self, x, y):
+		del self._chars[x+y*CHUNK_WIDTH]
+	
+	def apply(self, diff):
+		for i, c in diff._chars.items():
+			self._chars[i] = c
+	
+	def lines(self):
+		d = self._chars
+		s = "".join(d.get(i, " ") for i in range(CHUNK_WIDTH*CHUNK_HEIGHT))
+		return [s[i:i+CHUNK_WIDTH] for i in range(0, CHUNK_WIDTH*CHUNK_HEIGHT, CHUNK_WIDTH)]
+	
 
 class Chunk():
 	"""
@@ -17,7 +64,35 @@ class Chunk():
 	 - from accumulated changes
 	"""
 	
-	pass
+	def __init__(self):
+		self._content = ChunkDiff()
+		self._modifications = ChunkDiff()
+		
+		self.touch()
+	
+	def set(self, x, y, character):
+		self._modifications.set(x, y, character)
+	
+	def delete(self, x, y):
+		self._modifications.delete(x, y)
+	
+	def commit_changes(self):
+		self._content.apply(self._modifications)
+		self._modifications = ChunkDiff()
+	
+	def drop_changes(self):
+		self._modifications = ChunkDiff()
+	
+	def get_changes(self):
+		return self._modifications
+	
+	def touch(self):
+		self.last_modified = time.time()
+	
+	def draw_to(self, x, y, window):
+		for line in self._content.combine(self._modifications).lines():
+			window.addstr(y, x, line)
+			y += 1
 
 class ChunkPool():
 	"""
@@ -27,6 +102,7 @@ class ChunkPool():
 	"""
 	
 	def __init__(self):
+		self._chunks = {}
 		self._lock = threading.RLock()
 	
 	def __enter__(self):
@@ -36,8 +112,17 @@ class ChunkPool():
 	def __exit__(self, type, value, tb):
 		self._lock.release()
 	
-	def load_list(self, coords):
-		pass
+	def create(self, pos):
+		self._chunks[pos] = Chunk()
+		return self._chunks[pos]
 	
-	def get(self, x, y):
-		pass
+	def load(self, pos):
+		if not pos in self._chunks:
+			self.create(pos)
+	
+	def load_list(self, coords):
+		for pos in coords:
+			self.load(pos)
+	
+	def get(self, pos):
+		return self._chunks.get(pos)