Updated sprites and pet logic

scripts/split_sprite_sheet.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ $# -lt 4 || $# -gt 5 ]]; then
+  cat <<'EOF'
+Usage:
+  bash scripts/split_sprite_sheet.sh <sheet> <cell_width> <cell_height> <output_dir> [prefix]
+
+Example:
+  bash scripts/split_sprite_sheet.sh assets/pets/maple/spritesheet.webp 192 208 assets/pets/maple/frames maple
+
+Outputs:
+  <output_dir>/<prefix>-r01-c01.png
+  <output_dir>/<prefix>-r01-c02.png
+  ...
+
+Requirements:
+  - ffmpeg
+  - ffprobe
+EOF
+  exit 1
+fi
+
+sheet=$1
+cell_width=$2
+cell_height=$3
+output_dir=$4
+prefix=${5:-frame}
+
+if [[ ! -f "$sheet" ]]; then
+  echo "error: sheet not found: $sheet" >&2
+  exit 1
+fi
+
+if ! command -v ffmpeg >/dev/null 2>&1 || ! command -v ffprobe >/dev/null 2>&1; then
+  echo "error: ffmpeg and ffprobe are required" >&2
+  exit 1
+fi
+
+sheet_width=$(ffprobe -v error -select_streams v:0 -show_entries stream=width -of csv=p=0 "$sheet")
+sheet_height=$(ffprobe -v error -select_streams v:0 -show_entries stream=height -of csv=p=0 "$sheet")
+
+if (( sheet_width % cell_width != 0 )); then
+  echo "error: sheet width $sheet_width is not divisible by cell width $cell_width" >&2
+  exit 1
+fi
+
+if (( sheet_height % cell_height != 0 )); then
+  echo "error: sheet height $sheet_height is not divisible by cell height $cell_height" >&2
+  exit 1
+fi
+
+cols=$(( sheet_width / cell_width ))
+rows=$(( sheet_height / cell_height ))
+
+mkdir -p "$output_dir"
+
+for ((row = 0; row < rows; row++)); do
+  for ((col = 0; col < cols; col++)); do
+    x=$(( col * cell_width ))
+    y=$(( row * cell_height ))
+    out="$output_dir/${prefix}-r$(printf '%02d' $((row + 1)))-c$(printf '%02d' $((col + 1))).png"
+    ffmpeg -loglevel error -y -i "$sheet" -frames:v 1 -vf "crop=${cell_width}:${cell_height}:${x}:${y}" "$out"
+  done
+done
+
+echo "split complete: ${rows} rows x ${cols} cols -> $output_dir"