Add converter.py

README.md

@@ -1,2 +1,7 @@
-# KanjiVGToHanziWriterConverter
-A short python script that converts svg data from KanjiVG so that it can be used with HanziWriter.
+# KanjiVGToHanziWriterConverter  
+This python script can be used to convert svg files from [KanjiVG](https://kanjivg.tagaini.net) to a format usable with [HanziWriter](https://hanziwriter.org). Namely it converts all path elements to cubic Bézier curves and estimates medians via interpolation.  
+
+This script was use to generate the svg data for the Anki decks [常用漢字書き取り (Jouyou Kanji Writing Practice)](https://ankiweb.net/shared/info/536709674) and [常用外漢字書き取り (Jouyougai Kanji Writing Practice)](https://ankiweb.net/shared/info/1439997872).
+
+## License  
+This project is licensed under the MIT License.  

converter.py

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+from svgpathtools import svg2paths, CubicBezier
+
+
+def transform_point(point, shift: tuple[float, float] = (0., 0.), scale: tuple[float, float] = (0., 0.)):
+    return round(point.real * scale[0] + shift[0]) + round(point.imag * scale[1] + shift[1]) * 1j
+
+
+def transform_path(path, shift: tuple[float, float] = (0., 0.), scale: tuple[float, float] = (1., 1.)):
+    for part in path:
+        part.start = transform_point(part.start, shift, scale)
+        part.end = transform_point(part.end, shift, scale)
+        if isinstance(part, CubicBezier):
+            part.control1 = transform_point(part.control1, shift, scale)
+            part.control2 = transform_point(part.control2, shift, scale)
+    return path
+
+
+def get_transformed_paths(
+        file: str, shift: tuple[float, float] = (0., 0.), scale: tuple[float, float] = (1., 1.)
+) -> list[str]:
+    paths, _ = svg2paths(file)
+    paths = [transform_path(path, shift, scale) for path in paths]
+    return [path.d() for path in paths]
+
+
+def estimate_medians(
+        file: str, shift: tuple[float, float] = (0., 0.), scale: tuple[float, float] = (1., 1.), resolution: int = 5
+) -> list[list[list[int]]]:
+    medians = []
+    paths, _ = svg2paths(file)
+    for path in paths:
+        points = (path.point(i / (resolution - 1)) for i in range(resolution))
+        medians.append([[
+            round(point.real * scale[0] + shift[0]),
+            round(point.imag * scale[1] + shift[1])
+        ] for point in points])
+    return medians
+
+
+def get_strokes_and_medians(file: str, resolution: int = 5) -> dict:
+    """
+    Transforms SVG data from KanjiVG to HanziWriter format and then calculates the corresponding stroke and median data.
+
+    Parameters:
+    - file (str): The path to the SVG file from KanjiVG.
+    - resolution (int, optional): The resolution used in calculating the median data.
+      A higher resolution results in more detailed medians. Default value is 5.
+
+    Returns:
+    - dict: A dictionary containing two keys:
+        - 'strokes': A list of transformed stroke paths, formatted for HanziWriter.
+        - 'medians': The estimated median data for each stroke, calculated based on the specified resolution.
+
+    Example:
+    >>> svg_data = get_strokes_and_medians("kanji.svg")
+    >>> svg_data['strokes']  # List of stroke data
+    >>> svg_data['medians']  # Median information for each stroke
+    """
+    return {
+        "strokes": [v.replace(".0", "") for v in get_transformed_paths(file, (0., 900.), (1024 / 109, -1024 / 109))],
+        "medians": estimate_medians(file, (0., 900.), (1024 / 109, -1024 / 109), resolution)
+    }

requirements.txt

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+svgpathtools==1.5.1