Add original audit lantern pixel art

scripts/generate_pixel_art.py

@@ -0,0 +1,186 @@
+#!/usr/bin/env python3
+"""Generate the original pixel-art bounty asset for issue #80."""
+
+from __future__ import annotations
+
+import struct
+import zlib
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[1]
+OUT = ROOT / "assets" / "pixel-art" / "audit-lantern-grid.png"
+
+WIDTH = 128
+HEIGHT = 128
+
+PALETTE = {
+    "void": (10, 13, 20, 255),
+    "deep": (16, 23, 34, 255),
+    "grid": (28, 63, 70, 255),
+    "trace": (62, 172, 140, 255),
+    "trace_hi": (125, 238, 194, 255),
+    "gold": (235, 184, 76, 255),
+    "gold_hi": (255, 226, 132, 255),
+    "amber": (211, 112, 57, 255),
+    "shadow": (51, 36, 36, 255),
+    "glass": (115, 196, 213, 255),
+    "white": (235, 244, 241, 255),
+}
+
+
+def blank() -> list[list[tuple[int, int, int, int]]]:
+    return [[PALETTE["void"] for _ in range(WIDTH)] for _ in range(HEIGHT)]
+
+
+def dot(img: list[list[tuple[int, int, int, int]]], x: int, y: int, color: str) -> None:
+    if 0 <= x < WIDTH and 0 <= y < HEIGHT:
+        img[y][x] = PALETTE[color]
+
+
+def rect(
+    img: list[list[tuple[int, int, int, int]]],
+    x: int,
+    y: int,
+    w: int,
+    h: int,
+    color: str,
+) -> None:
+    for yy in range(y, y + h):
+        for xx in range(x, x + w):
+            dot(img, xx, yy, color)
+
+
+def line(
+    img: list[list[tuple[int, int, int, int]]],
+    x0: int,
+    y0: int,
+    x1: int,
+    y1: int,
+    color: str,
+) -> None:
+    dx = abs(x1 - x0)
+    sx = 1 if x0 < x1 else -1
+    dy = -abs(y1 - y0)
+    sy = 1 if y0 < y1 else -1
+    err = dx + dy
+    while True:
+        dot(img, x0, y0, color)
+        if x0 == x1 and y0 == y1:
+            return
+        twice = 2 * err
+        if twice >= dy:
+            err += dy
+            x0 += sx
+        if twice <= dx:
+            err += dx
+            y0 += sy
+
+
+def fill_circle(
+    img: list[list[tuple[int, int, int, int]]], cx: int, cy: int, radius: int, color: str
+) -> None:
+    r2 = radius * radius
+    for y in range(cy - radius, cy + radius + 1):
+        for x in range(cx - radius, cx + radius + 1):
+            if (x - cx) ** 2 + (y - cy) ** 2 <= r2:
+                dot(img, x, y, color)
+
+
+def pixelate_shadow(img: list[list[tuple[int, int, int, int]]]) -> None:
+    for y in range(0, HEIGHT, 4):
+        for x in range(0, WIDTH, 4):
+            if ((x * 17 + y * 23) % 37) in {0, 1, 2}:
+                rect(img, x, y, 2, 2, "deep")
+
+
+def draw_grid(img: list[list[tuple[int, int, int, int]]]) -> None:
+    for x in range(8, WIDTH, 12):
+        line(img, x, 10, x, 116, "grid")
+    for y in range(14, HEIGHT, 12):
+        line(img, 8, y, 119, y, "grid")
+
+    traces = [
+        (14, 97, 45, 97, 45, 76),
+        (82, 97, 111, 97, 111, 70),
+        (25, 35, 48, 35, 48, 55),
+        (101, 31, 82, 31, 82, 54),
+        (21, 74, 37, 74, 37, 62),
+        (92, 74, 109, 74, 109, 58),
+    ]
+    for x0, y0, x1, y1, x2, y2 in traces:
+        line(img, x0, y0, x1, y1, "trace")
+        line(img, x1, y1, x2, y2, "trace")
+        fill_circle(img, x0, y0, 2, "trace_hi")
+        fill_circle(img, x2, y2, 2, "trace_hi")
+
+
+def draw_lantern(img: list[list[tuple[int, int, int, int]]]) -> None:
+    fill_circle(img, 64, 62, 29, "amber")
+    fill_circle(img, 64, 62, 23, "gold")
+    fill_circle(img, 64, 62, 15, "gold_hi")
+
+    rect(img, 45, 42, 38, 48, "shadow")
+    rect(img, 49, 46, 30, 40, "glass")
+    rect(img, 53, 50, 22, 32, "deep")
+    rect(img, 57, 54, 14, 24, "gold_hi")
+    rect(img, 60, 58, 8, 16, "white")
+
+    rect(img, 42, 39, 44, 5, "gold")
+    rect(img, 47, 35, 34, 4, "gold_hi")
+    rect(img, 55, 30, 18, 5, "gold")
+    line(img, 58, 30, 58, 22, "gold_hi")
+    line(img, 70, 30, 70, 22, "gold_hi")
+    line(img, 58, 22, 70, 22, "gold")
+
+    rect(img, 42, 90, 44, 6, "gold")
+    rect(img, 49, 96, 30, 4, "gold_hi")
+    rect(img, 55, 100, 18, 4, "gold")
+
+    line(img, 50, 46, 78, 82, "trace_hi")
+    line(img, 78, 46, 50, 82, "trace_hi")
+    for x, y in [(52, 49), (75, 49), (52, 79), (75, 79)]:
+        fill_circle(img, x, y, 2, "white")
+
+
+def draw_foreground_marks(img: list[list[tuple[int, int, int, int]]]) -> None:
+    for x, y in [(20, 106), (33, 111), (94, 110), (108, 104), (17, 25), (111, 24)]:
+        rect(img, x, y, 5, 5, "gold")
+        rect(img, x + 1, y + 1, 3, 3, "gold_hi")
+    for x, y in [(30, 84), (98, 84), (64, 111), (64, 18)]:
+        fill_circle(img, x, y, 3, "trace_hi")
+        fill_circle(img, x, y, 1, "white")
+
+
+def write_png(path: Path, img: list[list[tuple[int, int, int, int]]]) -> None:
+    raw = b"".join(b"\x00" + b"".join(bytes(pixel) for pixel in row) for row in img)
+
+    def chunk(kind: bytes, data: bytes) -> bytes:
+        return (
+            struct.pack(">I", len(data))
+            + kind
+            + data
+            + struct.pack(">I", zlib.crc32(kind + data) & 0xFFFFFFFF)
+        )
+
+    path.parent.mkdir(parents=True, exist_ok=True)
+    path.write_bytes(
+        b"\x89PNG\r\n\x1a\n"
+        + chunk(b"IHDR", struct.pack(">IIBBBBB", WIDTH, HEIGHT, 8, 6, 0, 0, 0))
+        + chunk(b"IDAT", zlib.compress(raw, 9))
+        + chunk(b"IEND", b"")
+    )
+
+
+def main() -> None:
+    img = blank()
+    pixelate_shadow(img)
+    draw_grid(img)
+    draw_lantern(img)
+    draw_foreground_marks(img)
+    write_png(OUT, img)
+    print(OUT)
+
+
+if __name__ == "__main__":
+    main()