Update to Phosphor Icons V2.1.0 and a Script for Auto Updates (#18)

* Write script for automatic updates
New .tff font files are automatically downloaded from phosphoricons.com, and the rust code is generated for each variant.

* Update to Phosphor icons v2.1.0
Released Mar 31 2024. See https://github.com/phosphor-icons/homepage/releases/tag/v2.1.0

* Modify update script to not add duotone icons
After some testing, these icons don't seem to work with egui's font rendering.

scripts/update.py

@@ -0,0 +1,64 @@
+# This script downloads the latest version of the Phosphor Icons from the
+# official website, extracts the TTF files into the `res` directory, and
+# generates the rust code for each variant file.
+
+import io
+import json
+import requests
+import zipfile
+
+ICON_URL = "https://phosphoricons.com/assets/phosphor-icons.zip"
+
+# Download the latest version of the Phosphor Icons
+print(f"[*] Downloading Icons ({ICON_URL})")
+response = requests.get(ICON_URL)
+print(f"[*] Downloaded {len(response.content)} bytes")
+
+# Extract the TTF files and the code point to icon mappings from the
+# corresponding selection.json files
+variants = {}
+zip = zipfile.ZipFile(io.BytesIO(response.content))
+
+for info in zip.infolist():
+    if info.filename.endswith(".ttf"):
+        variant = info.filename.split("/")[1]
+        font = zip.read(info.filename)
+        info = json.loads(zip.read(f"Fonts/{variant}/selection.json"))
+
+        icons = {}
+        for icon in info["icons"]:
+            names = icon["properties"]["name"].split(", ")
+            for name in names:
+                icons[name] = icon["properties"]["code"]
+
+        variants[variant] = (font, icons)
+
+# Remove duotone variants as they don't seem to be supported by egui font
+# rendering
+if "duotone" in variants:
+    del variants["duotone"]
+
+print(f"[*] Found {len(variants)} variants ({', '.join(variants.keys())})")
+
+print("[*] Writing font and source files")
+for variant, (font, icons) in variants.items():
+    font_file = (
+        f"res/Phosphor-{variant[0].upper() + variant[1:]}.ttf"
+        if variant != "regular"
+        else "res/Phosphor.ttf"
+    )
+    with open(font_file, "wb") as file:
+        file.write(font)
+
+    with open(f"src/variants/{variant}.rs", "w") as file:
+        file.write("#![allow(unused)]\n")
+        for name, code in icons.items():
+            code_point = hex(code)[2:].upper()
+
+            name = name.replace("-", "_").upper()
+            if variant != "regular":
+                name = name[: -(len(variant) + 1)]
+
+            file.write(f'pub const {name}: &str = "\\u{{{code_point}}}";\n')
+
+print("[*] Done!")