Regenerate installer icon using full-size artwork

apps/desktop/scripts/generate_icon_assets.py

@@ -1,8 +1,10 @@
 #!/usr/bin/env python3
 """
-Generate optimized icon PNGs (32/64/128/256) with a tighter composition and rebuild icon.ico.
+Generate icon PNGs/ICO for the desktop installer using the high-resolution Raven artwork.
 
-This script avoids external imaging dependencies by parsing and writing PNGs directly.
+The script reads the square logo (`logo-raven-fund-azul.png`) and resizes it to the
+target sizes with a simple bilinear filter implemented with the Python standard library,
+avoiding additional dependencies.
 """
 
 from __future__ import annotations
@@ -14,11 +16,8 @@ from binascii import crc32
 from pathlib import Path
 
 ICON_DIR = Path(__file__).resolve().parents[1] / "src-tauri" / "icons"
-BASE_TRANSPARENT = ICON_DIR / "logo-raven.png"
+BASE_IMAGE = ICON_DIR / "logo-raven-fund-azul.png"
-BACKGROUND_SOURCE = ICON_DIR / "logo-raven-fund-azul.png"
-
 TARGET_SIZES = [32, 64, 128, 256, 512]
-FILL_RATIO = 0.9  # portion of the canvas occupied by the raven figure
 
 
 def read_png(path: Path) -> tuple[int, int, list[list[tuple[int, int, int, int]]]]:
@@ -27,7 +26,7 @@ def read_png(path: Path) -> tuple[int, int, list[list[tuple[int, int, int, int]]
     raise ValueError(f"{path} is not a PNG")
   pos = 8
   width = height = bit_depth = color_type = None
-  chunks: list[bytes] = []
+  compressed_parts = []
   while pos < len(data):
     length = struct.unpack(">I", data[pos : pos + 4])[0]
     pos += 4
@@ -35,18 +34,19 @@ def read_png(path: Path) -> tuple[int, int, list[list[tuple[int, int, int, int]]
     pos += 4
     chunk = data[pos : pos + length]
     pos += length
-    pos += 4  # CRC, ignored (validated by reader)
+    pos += 4  # CRC
     if ctype == b"IHDR":
       width, height, bit_depth, color_type, _, _, _ = struct.unpack(">IIBBBBB", chunk)
       if bit_depth != 8 or color_type not in (2, 6):
         raise ValueError("Only 8-bit RGB/RGBA PNGs are supported")
     elif ctype == b"IDAT":
-      chunks.append(chunk)
+      compressed_parts.append(chunk)
     elif ctype == b"IEND":
       break
   if width is None or height is None or bit_depth is None or color_type is None:
-    raise ValueError(f"{path} missing IHDR")
+    raise ValueError("PNG missing IHDR chunk")
-  raw = zlib.decompress(b"".join(chunks))
+
+  raw = zlib.decompress(b"".join(compressed_parts))
   bpp = 4 if color_type == 6 else 3
   stride = width * bpp
   rows = []
@@ -57,19 +57,19 @@ def read_png(path: Path) -> tuple[int, int, list[list[tuple[int, int, int, int]]
     idx += 1
     row = bytearray(raw[idx : idx + stride])
     idx += stride
-    if filter_type == 1:  # Sub
+    if filter_type == 1:
       for i in range(stride):
         left = row[i - bpp] if i >= bpp else 0
         row[i] = (row[i] + left) & 0xFF
-    elif filter_type == 2:  # Up
+    elif filter_type == 2:
       for i in range(stride):
         row[i] = (row[i] + prev[i]) & 0xFF
-    elif filter_type == 3:  # Average
+    elif filter_type == 3:
       for i in range(stride):
         left = row[i - bpp] if i >= bpp else 0
         up = prev[i]
         row[i] = (row[i] + ((left + up) // 2)) & 0xFF
-    elif filter_type == 4:  # Paeth
+    elif filter_type == 4:
       for i in range(stride):
         left = row[i - bpp] if i >= bpp else 0
         up = prev[i]
@@ -89,24 +89,20 @@ def read_png(path: Path) -> tuple[int, int, list[list[tuple[int, int, int, int]]
       raise ValueError(f"Unsupported PNG filter type {filter_type}")
     rows.append(bytes(row))
     prev[:] = row
+
   pixels: list[list[tuple[int, int, int, int]]] = []
   for row in rows:
-    row_pixels = []
     if color_type == 6:
-      for i in range(0, len(row), 4):
+      pixels.append([tuple(row[i : i + 4]) for i in range(0, len(row), 4)])
-        row_pixels.append(tuple(row[i : i + 4]))
     else:
-      for i in range(0, len(row), 3):
+      pixels.append([tuple(row[i : i + 3] + b"\xff") for i in range(0, len(row), 3)])
-        r, g, b = row[i : i + 3]
-        row_pixels.append((r, g, b, 255))
-    pixels.append(row_pixels)
   return width, height, pixels
 
 
 def write_png(path: Path, width: int, height: int, pixels: list[list[tuple[int, int, int, int]]]) -> None:
   raw = bytearray()
   for row in pixels:
-    raw.append(0)  # no filter
+    raw.append(0)  # filter type 0
     for r, g, b, a in row:
       raw.extend((r & 0xFF, g & 0xFF, b & 0xFF, a & 0xFF))
   compressed = zlib.compress(raw, level=9)
@@ -127,83 +123,50 @@ def write_png(path: Path, width: int, height: int, pixels: list[list[tuple[int,
   path.write_bytes(out)
 
 
-def crop_content(pixels: list[list[tuple[int, int, int, int]]]) -> list[list[tuple[int, int, int, int]]]:
+def bilinear_sample(pixels: list[list[tuple[int, int, int, int]]], x: float, y: float) -> tuple[int, int, int, int]:
   height = len(pixels)
   width = len(pixels[0])
-  min_x, min_y = width, height
+  x = min(max(x, 0.0), width - 1.0)
-  max_x = max_y = -1
+  y = min(max(y, 0.0), height - 1.0)
-  for y, row in enumerate(pixels):
-    for x, (_, _, _, a) in enumerate(row):
-      if a > 0:
-        if x < min_x:
-          min_x = x
-        if y < min_y:
-          min_y = y
-        if x > max_x:
-          max_x = x
-        if y > max_y:
-          max_y = y
-  if max_x < min_x or max_y < min_y:
-    return pixels
-  cropped = [row[min_x : max_x + 1] for row in pixels[min_y : max_y + 1]]
-  return cropped
-
-
-def bilinear_sample(data: list[list[tuple[int, int, int, int]]], x: float, y: float) -> tuple[int, int, int, int]:
-  height = len(data)
-  width = len(data[0])
-  if x < 0:
-    x = 0
-  if y < 0:
-    y = 0
-  if x > width - 1:
-    x = width - 1
-  if y > height - 1:
-    y = height - 1
   x0 = int(math.floor(x))
-  x1 = min(x0 + 1, width - 1)
   y0 = int(math.floor(y))
+  x1 = min(x0 + 1, width - 1)
   y1 = min(y0 + 1, height - 1)
   dx = x - x0
   dy = y - y0
+
   def lerp(a: float, b: float, t: float) -> float:
     return a + (b - a) * t
+
   result = []
   for channel in range(4):
-    c00 = data[y0][x0][channel]
+    c00 = pixels[y0][x0][channel]
-    c10 = data[y0][x1][channel]
+    c10 = pixels[y0][x1][channel]
-    c01 = data[y1][x0][channel]
+    c01 = pixels[y1][x0][channel]
-    c11 = data[y1][x1][channel]
+    c11 = pixels[y1][x1][channel]
     top = lerp(c00, c10, dx)
     bottom = lerp(c01, c11, dx)
-    value = lerp(top, bottom, dy)
+    result.append(int(round(lerp(top, bottom, dy))))
-    result.append(int(round(value)))
   return tuple(result)
 
 
-def resize_with_background(
+def resize_image(pixels: list[list[tuple[int, int, int, int]]], target: int) -> list[list[tuple[int, int, int, int]]]:
-  src: list[list[tuple[int, int, int, int]]],
+  src_height = len(pixels)
-  canvas_size: int,
+  src_width = len(pixels[0])
-  fill_ratio: float,
+  scale = min(target / src_width, target / src_height)
-  background: tuple[int, int, int],
+  dest_width = max(1, int(round(src_width * scale)))
-) -> list[list[tuple[int, int, int, int]]]:
+  dest_height = max(1, int(round(src_height * scale)))
-  src_h = len(src)
+  offset_x = (target - dest_width) // 2
-  src_w = len(src[0])
+  offset_y = (target - dest_height) // 2
-  scale = fill_ratio * min(canvas_size / src_w, canvas_size / src_h)
+
-  dest_w = max(1, int(round(src_w * scale)))
+  background = (0, 0, 0, 0)
-  dest_h = max(1, int(round(src_h * scale)))
+  canvas = [[background for _ in range(target)] for _ in range(target)]
-  offset_x = (canvas_size - dest_w) // 2
+
-  offset_y = (canvas_size - dest_h) // 2
+  for dy in range(dest_height):
-  canvas = [
-    [(background[0], background[1], background[2], 255) for _ in range(canvas_size)]
-    for _ in range(canvas_size)
-  ]
-  for dy in range(dest_h):
     src_y = (dy + 0.5) / scale - 0.5
-    for dx in range(dest_w):
+    for dx in range(dest_width):
       src_x = (dx + 0.5) / scale - 0.5
-      r, g, b, a = bilinear_sample(src, src_x, src_y)
+      canvas[offset_y + dy][offset_x + dx] = bilinear_sample(pixels, src_x, src_y)
-      canvas[offset_y + dy][offset_x + dx] = (r, g, b, a)
   return canvas
 
 
@@ -213,18 +176,15 @@ def build_ico(output: Path, png_paths: list[Path]) -> None:
   for path in png_paths:
     data = path.read_bytes()
     width, height, _ = read_png(path)
-    entry = {
+    entries.append(
-      "width": width if width < 256 else 0,
+      {
-      "height": height if height < 256 else 0,
+        "width": width if width < 256 else 0,
-      "colors": 0,
+        "height": height if height < 256 else 0,
-      "reserved": 0,
+        "size": len(data),
-      "planes": 1,
+        "offset": offset,
-      "bit_count": 32,
+        "payload": data,
-      "size": len(data),
+      }
-      "offset": offset,
+    )
-      "data": data,
-    }
-    entries.append(entry)
     offset += len(data)
 
   header = struct.pack("<HHH", 0, 1, len(entries))
@@ -235,46 +195,43 @@ def build_ico(output: Path, png_paths: list[Path]) -> None:
         "<BBBBHHII",
         entry["width"],
         entry["height"],
-        entry["colors"],
+        0,
-        entry["reserved"],
+        0,
-        entry["planes"],
+        1,
-        entry["bit_count"],
+        32,
         entry["size"],
         entry["offset"],
       )
     )
   for entry in entries:
-    body.extend(entry["data"])
+    body.extend(entry["payload"])
   output.write_bytes(body)
 
 
 def main() -> None:
-  base_w, base_h, base_pixels = read_png(BASE_TRANSPARENT)
+  width, height, pixels = read_png(BASE_IMAGE)
-  background_w, background_h, bg_pixels = read_png(BACKGROUND_SOURCE)
+  if width != height:
-  background_color = bg_pixels[background_h // 2][background_w // 2][:3]
+    raise ValueError("Base icon must be square")
-
-  cropped = crop_content(base_pixels)
 
   generated: list[Path] = []
   for size in TARGET_SIZES:
-    dest_pixels = resize_with_background(cropped, size, FILL_RATIO, background_color)
+    resized = resize_image(pixels, size)
     out_path = ICON_DIR / f"icon-{size}.png"
-    write_png(out_path, size, size, dest_pixels)
+    write_png(out_path, size, size, resized)
     generated.append(out_path)
     print(f"Generated {out_path} ({size}x{size})")
 
-  # Update base PNG used by some bundlers
+  largest = max(generated, key=lambda p: int(p.stem.split("-")[-1]))
-  biggest = max(generated, key=lambda p: int(p.stem.split("-")[-1]))
+  (ICON_DIR / "icon.png").write_bytes(largest.read_bytes())
-  (ICON_DIR / "icon.png").write_bytes(biggest.read_bytes())
 
-  # Build ICO with largest size first (common preference)
+  ico_sources = sorted(
-  ordered = sorted(
     [p for p in generated if int(p.stem.split("-")[-1]) <= 256],
     key=lambda p: int(p.stem.split("-")[-1]),
   )
-  build_ico(ICON_DIR / "icon.ico", ordered)
+  build_ico(ICON_DIR / "icon.ico", ico_sources)
-  print("icon.ico rebuilt with revised artwork.")
+  print("icon.ico rebuilt.")
 
 
 if __name__ == "__main__":
   main()
+