Highlight key rule for Crowded House, issue #3.

Fix font bug, and switch to Cairo for converting SVG to PNG.

diagram.py

@@ -31,7 +31,7 @@ def build(self) -> SvgDiagram:
         square_size = 45
         x0 = 15 - 0.5*square_size
         y0 = 9.112 * square_size
-        text_elements = Drawing()
+        extra_elements = Drawing()
         text_args = dict(text_anchor='middle',
                          font_family='Raleway',
                          font_size=round(0.55*square_size))
@@ -42,17 +42,30 @@ def build(self) -> SvgDiagram:
             if command == 'text':
                 x = round(x0 + float(fields[1]) * square_size, 1)
                 y = round(y0 - float(fields[2]) * square_size, 1)
-                # fields[0] = str(y)
-                text_elements.add(text_elements.text(fields[0],
-                                                     (x, y),
-                                                     **text_args))
+                extra_elements.add(extra_elements.text(fields[0],
+                                                       (x, y),
+                                                       **text_args))
+            elif command == 'rect':
+                x1, y1, x2, y2 = [float(field) for field in fields]
+                left = round(15 + (x1-1)*square_size, 1)
+                top = round(15 + (8 - y2) * square_size, 1)
+                width = round((x2-x1+1)*square_size, 1)
+                height = round((y2-y1+1)*square_size, 1)
+                extra_elements.add(extra_elements.rect((left, top),
+                                                       (width, height),
+                                                       fill_opacity=0,
+                                                       stroke='blue',
+                                                       stroke_width=5,
+                                                       stroke_dasharray='7.5'))
             elif command == 'margins':
                 margins = tuple(float(n) for n in fields[:2])
-            else:
+            elif command == 'arrow':
                 tail = getattr(chess, fields[0].upper())
                 head = getattr(chess, fields[1].upper())
                 colour = fields[2]
                 arrows.append(chess.svg.Arrow(tail, head, color=colour))
+            else:
+                raise ValueError(f'Unknown diagram command: {command}.')
         original_view_size = 390  # chess library always uses this size
         view_width = original_view_size + 2*margins[0]*square_size
         view_height = original_view_size + 2*margins[1]*square_size
@@ -69,7 +82,7 @@ def build(self) -> SvgDiagram:
         board_tree.set('viewBox', view_box)
         board_tree.set('width', str(image_width))
         board_tree.set('height', str(image_height))
-        board_tree.extend(text_elements.get_xml())
+        board_tree.extend(extra_elements.get_xml())
 
         diagram = SvgDiagram(ET.tostring(board_tree, encoding='unicode'))
         return diagram

diagram_differ.py

@@ -19,12 +19,8 @@ def convert_to_png(self) -> bytes:
         self.write_png(png_alpha_bytes)
         return png_alpha_bytes.getvalue()
 
-    def write_png(self, file: typing.Union[typing.BinaryIO, Path]):
-        drawing = self.diagram.to_reportlab()
-        png_bytes = BytesIO(drawToString(drawing, 'PNG'))
-        image = Image.open(png_bytes)
-        image_alpha = image.convert('RGBA')
-        image_alpha.save(file, 'PNG')
+    def write_png(self, file: typing.BinaryIO | Path | str):
+        self.diagram.to_cairo(file)
 
     def save(self, file_path: Path) -> Path:
         """ Save the image to a file.

docs/new_rules.md

@@ -33,12 +33,15 @@ play order would be Walter, Betty, Winnie, Bob, Walter, Betty, and so on.
 ![Diagram](images/new_rules/diagram1.png)
 
 ### Rule changes
-The key rule is that you may only move a piece that either starts or ends on
-your side of the board.
+The key rule is that you may only move a piece that either
 
-In this example, Winnie may move the bishop as shown, because it ends up on the
-queen side of the board. Winnie may not move the bishop to e2, because it would
-start and end on the king side.
+* **starts** on your side of the board, or
+* **ends** on your side of the board.
+
+In this example, Winnie may move any piece that starts or ends on the queen
+side of the board, shown by the dashed rectangle. She may move the bishop as
+shown by the arrow, because it ends up on the queen side of the board. Winnie
+may not move the bishop to e2, because it would start and end on the king side.
 
 ![Diagram](images/new_rules/diagram2.png)
 
@@ -55,10 +58,10 @@ Win by check mate, as usual, but remember that the next player on the attacking
 team has to be able to make the capture.
 
 ### Talking
-This is a silly game, so feel free to chat with your partner, but remember that
-the other team is listening. Any discussion should be heard by both teams, so
-no secret codes or second languages! Of course, players should also feel free to
-ignore their partner's advice.
+This game shouldn't be taken too seriously, so feel free to chat with your
+partner, but remember that the other team is listening. Any discussion should
+be heard by both teams, so no secret codes or second languages! Of course,
+players should also feel free to ignore their partner's advice.
 
 # Broken Games
 These ideas seemed promising, but didn't work at the table. Maybe I'll come back

font_set.py

@@ -13,16 +13,18 @@ def register_fonts(include_courier=False):
     raleway_italic_file = fonts_path / 'Raleway' / 'static' / 'Raleway-Italic.ttf'
     raleway_bold_italic_file = fonts_path / 'Raleway' / 'static' / 'Raleway-BoldItalic.ttf'
     courier_file = fonts_path / 'Courier_Prime' / 'CourierPrime-Regular.ttf'
-    pdfmetrics.registerFont(TTFont("Fredoka", fredoka_file))
-    pdfmetrics.registerFont(TTFont("Raleway", raleway_file))
-    pdfmetrics.registerFont(TTFont("Raleway-Bold", raleway_bold_file))
-    pdfmetrics.registerFont(TTFont("Raleway-Italic", raleway_italic_file))
-    pdfmetrics.registerFont(TTFont("Raleway-BoldItalic", raleway_bold_italic_file))
-    pdfmetrics.registerFontFamily('Raleway',
-                                  'Raleway',
-                                  'Raleway-Bold',
-                                  'Raleway-Italic',
-                                  'Raleway-BoldItalic')
+    # If we use the regular names, then there can be collisions between fonts in
+    # SVG diagrams and the main body of the document.
+    pdfmetrics.registerFont(TTFont("Heading", fredoka_file))
+    pdfmetrics.registerFont(TTFont("Body", raleway_file))
+    pdfmetrics.registerFont(TTFont("Body-Bold", raleway_bold_file))
+    pdfmetrics.registerFont(TTFont("Body-Italic", raleway_italic_file))
+    pdfmetrics.registerFont(TTFont("Body-BoldItalic", raleway_bold_italic_file))
+    pdfmetrics.registerFontFamily('Body',
+                                  'Body',
+                                  'Body-Bold',
+                                  'Body-Italic',
+                                  'Body-BoldItalic')
     if include_courier:
         pdfmetrics.registerFont(TTFont("Courier", courier_file))
         pdfmetrics.registerFontFamily('Courier',

publish_rules.py

@@ -200,21 +200,21 @@ def main():
         if hasattr(style, 'fontSize'):
             if style.name.startswith('Heading'):
                 scale = 1.5
-                style.fontName = 'Fredoka'
+                style.fontName = 'Heading'
             else:
                 scale = 2
-                style.fontName = 'Raleway'
+                style.fontName = 'Body'
             if False and args.booklet:
                 style.fontSize *= scale
                 style.leading *= scale
     paragraph_style = styles[Styles.Normal]
     numbered_list_style = ListStyle('default_list',
-                                    bulletFontName='Raleway',
+                                    bulletFontName='Body',
                                     bulletFontSize=paragraph_style.fontSize,
                                     leftIndent=paragraph_style.fontSize * 1.5,
                                     bulletFormat='%s.')
     bulleted_list_style = ListStyle('default_list',
-                                    bulletFontName='Raleway',
+                                    bulletFontName='Body',
                                     bulletFontSize=paragraph_style.fontSize,
                                     leftIndent=paragraph_style.fontSize * 1.5)
     centred_style = ParagraphStyle('Author',
@@ -265,7 +265,7 @@ def main():
                 subtitle_style = ParagraphStyle('Subtitle',
                                                 parent=paragraph_style,
                                                 alignment=TA_CENTER,
-                                                fontName='Raleway-Italic')
+                                                fontName='Body-Italic')
                 story.append(Paragraph(subtitle_text, subtitle_style))
             if args.booklet:
                 story.append(Spacer(0, page_size[1] * 0.15))
@@ -362,7 +362,7 @@ def main():
                                    ', '.join(unlinked_section_names))
         raise ValueError(unknown_section_message)
     doc.multiBuild(story, canvasmaker=partial(FooterCanvas,
-                                              font_name='Raleway',
+                                              font_name='Body',
                                               is_booklet=args.booklet))
     if not args.no_merge:
         with merged_path.open('w') as merged_file:

raw_rules/new_rules.md

@@ -36,12 +36,15 @@ play order would be Walter, Betty, Winnie, Bob, Walter, Betty, and so on.
     text: 4: Bob, -1.5, 8
 
 ### Rule changes
-The key rule is that you may only move a piece that either starts or ends on
-your side of the board.
+The key rule is that you may only move a piece that either
 
-In this example, Winnie may move the bishop as shown, because it ends up on the
-queen side of the board. Winnie may not move the bishop to e2, because it would
-start and end on the king side.
+* **starts** on your side of the board, or
+* **ends** on your side of the board.
+
+In this example, Winnie may move any piece that starts or ends on the queen
+side of the board, shown by the dashed rectangle. She may move the bishop as
+shown by the arrow, because it ends up on the queen side of the board. Winnie
+may not move the bishop to e2, because it would start and end on the king side.
 
     r n b q k b n r
     p p p p . p p p
@@ -57,6 +60,7 @@ start and end on the king side.
     text: 2: Betty, 10.5, 8
     text: 3: Winnie, -1.5, 1
     text: 4: Bob, -1.5, 8
+    rect: 1, 1, 4, 8
 
 If a player has no pieces on their side and can't move any pieces to their side,
 they move nothing on that turn.
@@ -71,10 +75,10 @@ Win by check mate, as usual, but remember that the next player on the attacking
 team has to be able to make the capture.
 
 ### Talking
-This is a silly game, so feel free to chat with your partner, but remember that
-the other team is listening. Any discussion should be heard by both teams, so
-no secret codes or second languages! Of course, players should also feel free to
-ignore their partner's advice.
+This game shouldn't be taken too seriously, so feel free to chat with your
+partner, but remember that the other team is listening. Any discussion should
+be heard by both teams, so no secret codes or second languages! Of course,
+players should also feel free to ignore their partner's advice.
 
 # Broken Games
 These ideas seemed promising, but didn't work at the table. Maybe I'll come back

svg_diagram.py

@@ -1,5 +1,6 @@
 import typing
 from io import BytesIO, StringIO
+from pathlib import Path
 
 import reportlab.graphics.shapes as reportlab_shapes
 from cairosvg import svg2png
@@ -15,7 +16,9 @@ def to_reportlab(self) -> reportlab_shapes.Drawing:
         drawing = svg2rlg(BytesIO(svg_bytes))
         return drawing
 
-    def to_cairo(self, png_file: str | typing.BinaryIO):
+    def to_cairo(self, png_file: str | Path | typing.BinaryIO):
+        if isinstance(png_file, Path):
+            png_file = str(png_file)
         svg2png(file_obj=StringIO(self.svg_text),
                 write_to=png_file,
                 background_color='transparent')

tests/test_diagram.py

@@ -116,7 +116,7 @@ def test_text(diagram_differ: DiagramDiffer):
 
 
 # noinspection DuplicatedCode
-def test_offset(diagram_differ: DiagramDiffer):
+def test_margins(diagram_differ: DiagramDiffer):
     diagram_text = dedent("""\
         . . . k q . . .
         . . . . . . . .
@@ -146,7 +146,6 @@ def test_offset(diagram_differ: DiagramDiffer):
     extra = Drawing(size=(300, 240))
     extra.add(extra.text('A2', (37.5, 320), **text_args))
     extra.add(extra.text('G3', (307.5, 275), **text_args))
-    # extra.add(extra.rect((390+45, 15), (45, 45)))
     expected_tree.extend(extra.get_xml())
     expected_diagram = SvgDiagram(ET.tostring(expected_tree,
                                               encoding='unicode'))
@@ -157,6 +156,62 @@ def test_offset(diagram_differ: DiagramDiffer):
     diagram_differ.assert_equal(svg_diagram, expected_diagram)
 
 
+# noinspection DuplicatedCode
+def test_rect(diagram_differ: DiagramDiffer):
+    diagram_text = dedent("""\
+        . . . k q . . .
+        . . . . . . . .
+        . . . . . . . .
+        . . . . Q . . .
+        . . . P . . . .
+        . . . . . . . .
+        . . . . . . . .
+        . . . K . . . .
+        rect: 2, 6, 5, 7
+        """)
+    expected_text = diagram_text.split('rect')[0]
+    expected_board = parse_board(expected_text)
+    expected_board_svg = chess.svg.board(
+        expected_board,
+        size=195)
+    Diagram.register_svg()
+    expected_tree = ET.fromstring(expected_board_svg)
+    extra = Drawing(size=(300, 240))
+    extra.add(extra.rect((60, 60),
+                         (180, 90),
+                         fill_opacity=0,
+                         stroke='blue',
+                         stroke_dasharray='7.5',
+                         stroke_width=5))
+    expected_tree.extend(extra.get_xml())
+    expected_diagram = SvgDiagram(ET.tostring(expected_tree,
+                                              encoding='unicode'))
+
+    diagram = Diagram(390, 195, diagram_text)
+    svg_diagram = diagram.build()
+
+    diagram_differ.assert_equal(svg_diagram, expected_diagram)
+
+
+# noinspection DuplicatedCode
+def test_unknown(diagram_differ: DiagramDiffer):
+    diagram_text = dedent("""\
+        . . . k q . . .
+        . . . . . . . .
+        . . . . . . . .
+        . . . . Q . . .
+        . . . P . . . .
+        . . . . . . . .
+        . . . . . . . .
+        . . . K . . . .
+        bogus: What is this?
+        """)
+
+    diagram = Diagram(570, 240, diagram_text)
+    with pytest.raises(ValueError, match=r'Unknown diagram command: bogus'):
+        diagram.build()
+
+
 # noinspection DuplicatedCode
 def test_masquerade(diagram_differ: DiagramDiffer):
     diagram_text = dedent("""\