1 files changed, 122 insertions, 0 deletions
diff --git a/gbimg.py b/gbimg.py
new file mode 100644
index 0000000..6a3613f
--- /dev/null
+++ b/gbimg.py
@@ -0,0 +1,122 @@
+#! /usr/bin/env python3
+##
+##  gbimg - turn PC image files into Game Boy tilesets
+##  Copyright (C) 2016 Delwink, LLC
+##
+##  This program is free software: you can redistribute it and/or modify
+##  it under the terms of the GNU Affero General Public License as published by
+##  the Free Software Foundation, version 3 only.
+##
+##  This program is distributed in the hope that it will be useful,
+##  but WITHOUT ANY WARRANTY; without even the implied warranty of
+##  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+##  GNU Affero General Public License for more details.
+##
+##  You should have received a copy of the GNU Affero General Public License
+##  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+##
+
+from wand.image import Image
+
+_PALETTE = {
+    0:   3,
+    85:  2,
+    170: 1,
+    255: 0
+}
+
+def map_palette(color):
+    if color not in _PALETTE:
+        raise ValueError('{} is not a valid color level'.format(color))
+
+    return _PALETTE[color]
+
+class Tileset:
+    def __init__(self, img, data, bank=None):
+        self._img = img
+        self._data = None
+        self._data_var = data
+
+        if type(bank) is str:
+            self._bank_var = bank
+            self._bank_num = None
+        elif type(bank) is int:
+            self._bank_var = None
+            self._bank_num = bank
+        elif bank is None:
+            self._bank_var = None
+            self._bank_num = None
+        else:
+            raise TypeError('bank must be str, int, or None')
+
+    def set_bank_num(self, num):
+        self._bank_num = num
+
+    def _convert(self):
+        with Image(filename=self._img) as img:
+            width, height = img.size
+            if height != 8:
+                raise ValueError('{} height is {}'.format(self, height))
+
+            num_tiles = width / 8
+            if num_tiles % 1 != 0:
+                raise ValueError('Irregular tile width in {}'.format(self))
+
+            num_tiles = int(num_tiles)
+            img.depth = 8
+            blob = img.make_blob(format='RGB')
+
+        encoded = []
+        for tile in range(num_tiles):
+            encoded_tile = []
+
+            for i in range(0, width * 8 * 3, width * 3):
+                byte1 = 0
+                byte2 = 0
+                bit = 0x80
+
+                for j in range(0, 8 * 3, 3):
+                    color = map_palette(blob[(i + j) + ((8 * 3) * tile)])
+
+                    if color & 0x02:
+                        byte1 |= bit
+                    if color & 0x01:
+                        byte2 |= bit
+
+                    bit >>= 1
+
+                encoded_tile.append(byte1)
+                encoded_tile.append(byte2)
+
+            encoded += encoded_tile
+
+        return bytes(encoded)
+
+    @property
+    def data(self):
+        if not self._data:
+            self._data = self._convert()
+
+        return self._data
+
+    @property
+    def image_file(self):
+        return self._img
+
+    @property
+    def data_var(self):
+        return self._data_var
+
+    @property
+    def bank_var(self):
+        return self._bank_var
+
+    @property
+    def bank_num(self):
+        return self._bank_num
+
+    def __len__(self):
+        return len(self.data)
+
+    def __str__(self):
+        return 'Tileset ' + self.image_file