textgen: cleanup

Make the classes self-contained
Make the functions re-entrant

graphics/text/smtextgen.py

@@ -12,21 +12,16 @@ import re
 from image_dimensions import *
 from tint import image_tint
 
-# Background color for output files.
-BACKGROUND_COLOR = None
-
-# Width of a space character in pixels.
-SPACE_WIDTH = 4
-
-# Height of the font.
-FONT_HEIGHT = 8
-
-# Regexp to match dimensions/x,y coordinate pair.
 DIMENSION_MATCH_RE = re.compile(r'(\d+)[x,](\d+)')
 
-class Font(object):
+class SmallTextGenerator(object):
 	def __init__(self):
 		self.get_font_widths()
+	# Width of a space character in pixels.
+	SPACE_WIDTH = 4
+	# Height of the font.
+	FONT_HEIGHT = 8
+	# Regexp to match dimensions/x,y coordinate pair.
 
 	def compile_kerning_table(self, kerning_table):
 		"""Given a dictionary of kerning patterns, compile Regexps."""
@@ -57,15 +52,15 @@ class Font(object):
 
 	def draw_for_text(self, image, text, x, y):
 		text = text.upper()
-
+		new_image = image.copy()
 		x1, y1 = x, y
 
 		for c in text:
 			if c == '\n':
-				y1 += FONT_HEIGHT
+				y1 += self.FONT_HEIGHT
 				x1 = x
 			elif c == ' ':
-				x1 += SPACE_WIDTH
+				x1 += self.SPACE_WIDTH
 
 			if c not in self:
 				continue
@@ -73,13 +68,15 @@ class Font(object):
 			filename = self.char_filename(c)
 			char_image = Image.open(filename)
 			char_image.load()
-			self.paste_image(image, char_image, x1, y1)
+			new_image = self.paste_image(new_image, char_image, x1, y1)
 			x1 += self.char_width(c)
+		return new_image
 
 	def paste_image(self, image, src, x, y):
 		int_image = Image.new("RGBA", image.size, (0, 0, 0, 0))
 		int_image.paste(src, (x, y))
-		image = Image.alpha_composite(image, int_image)
+		new_image = Image.alpha_composite(image, int_image)
+		return new_image
 
 
 def parse_command_line(args):
@@ -126,7 +123,7 @@ if __name__ == '__main__':
 		print("  [x,y] [text]")
 		sys.exit(0)
 
-	smallfont = Font()
+	smallfont = SmallTextGenerator()
 
 	if args['background'] is not None:
 		background_image = Image.open(args['background'])
@@ -146,9 +143,9 @@ if __name__ == '__main__':
 		if string.startswith('file:'):
 			src_image = Image.open(string[5:])
 			src_image.load()
-			smallfont.paste_image(image, src_image, xy[0], xy[1])
+			image = smallfont.paste_image(image, src_image, xy[0], xy[1])
 		else:
-			smallfont.draw_for_text(image, string, xy[0], xy[1])
+			image = smallfont.draw_for_text(image, string, xy[0], xy[1])
 
 	if args['background'] is not None:
 		image = Image.alpha_composite(background_image, image)

graphics/text/textgen.py

@@ -14,32 +14,30 @@ from config import *
 from image_dimensions import *
 from tint import image_tint
 
-# Tinting parameters for colorizing text:
-COLOR_BLUE = "#000001"
-COLOR_RED = "#010000"
-COLOR_WHITE = None
-
-# Background color for output files.
-BACKGROUND_COLOR = None
-
-# Height of font in pixels.
-FONT_HEIGHT = 15
-FONT_LC_HEIGHT = 15  # 12
-
-# If true, the font only has uppercase characters.
-UPPERCASE_FONT = False
-
-# Width of a space character in pixels.
-SPACE_WIDTH = 7
-LOWERCASE_RE = re.compile(r'^[a-z\!\. ]*$')
 
 
-class Font(object):
+class TextGenerator(object):
 	def __init__(self, fontdir, kerning_table={}):
 		self.fontdir = fontdir
 		self.kerning_table = self.compile_kerning_table(kerning_table)
 		self.get_font_widths()
 
+	# Tinting parameters for colorizing text:
+	COLOR_BLUE = "#000001"
+	COLOR_RED = "#010000"
+	COLOR_WHITE = None
+
+	# Height of font in pixels.
+	FONT_HEIGHT = 15
+	FONT_LC_HEIGHT = 15  # 12
+
+	# If true, the font only has uppercase characters.
+	UPPERCASE_FONT = False
+
+	# Width of a space character in pixels.
+	SPACE_WIDTH = 7
+	LOWERCASE_RE = re.compile(r'^[a-z\!\. ]*$')
+
 	def compile_kerning_table(self, kerning_table):
 		"""Given a dictionary of kerning patterns, compile Regexps."""
 
@@ -87,7 +85,7 @@ class Font(object):
 		last_c = ' '
 		for c in text:
 			if c == ' ':
-				x += SPACE_WIDTH
+				x += self.SPACE_WIDTH
 
 			if c in self:
 				x += self.kerning_adjust(last_c, c)
@@ -110,20 +108,20 @@ class Font(object):
 			if c is None:
 				return x
 
-	def generate_graphic(self, text, color=COLOR_WHITE):
+	def generate_graphic(self, text, color=None):
 		"""Get command to render text to a file
 		   with the given background color.
 		"""
 
-		if UPPERCASE_FONT:
+		if self.UPPERCASE_FONT:
 			text = text.upper()
 		"""Command line construction helper, used in render functions"""
 		width = self.text_width(text)
 
-		if LOWERCASE_RE.match(text):
+		if self.LOWERCASE_RE.match(text):
-			height = FONT_LC_HEIGHT
+			height = self.FONT_LC_HEIGHT
 		else:
-			height = FONT_HEIGHT
+			height = self.FONT_HEIGHT
 
 		txt_image = Image.new("RGBA", (width, height), (0, 0, 0, 0))
 		for c, x in self.iterate_char_positions(text):
@@ -134,14 +132,14 @@ class Font(object):
 			char_image = Image.open(filename)
 			char_image.load()
 			int_image = Image.new("RGBA", txt_image.size, (0, 0, 0, 0))
-			int_image.paste(char_image, (x, height - FONT_HEIGHT))
+			int_image.paste(char_image, (x, height - self.FONT_HEIGHT))
 			txt_image = Image.alpha_composite(txt_image, int_image)
 
 		txt_image = image_tint(txt_image, color)
 		return txt_image
 
 
-def generate_graphics(graphics, color=COLOR_WHITE):
+def generate_graphics(font, graphics, color=None):
 	for name, text in sorted(graphics.items()):
 		# write a makefile fragment
 		target = '%s.png' % name
@@ -149,7 +147,7 @@ def generate_graphics(graphics, color=COLOR_WHITE):
 		image.save(target)
 
 
-def generate_kerning_test():
+def generate_kerning_test(font):
 	pairs = []
 	for c1 in sorted(font.char_widths):
 		char1 = "%c" % c1
@@ -162,7 +160,7 @@ def generate_kerning_test():
 
 if __name__ == '__main__':
 
-	font = Font('fontchars', kerning_table=FONT_KERNING_RULES)
+	font = TextGenerator('fontchars', kerning_table=FONT_KERNING_RULES)
-	generate_graphics(red_graphics, color=COLOR_RED)
+	generate_graphics(font, red_graphics, color=font.COLOR_RED)
-	generate_graphics(blue_graphics, color=COLOR_BLUE)
+	generate_graphics(font, blue_graphics, color=font.COLOR_BLUE)
-	generate_graphics(white_graphics, color=COLOR_WHITE)
+	generate_graphics(font, white_graphics, color=font.COLOR_WHITE)