add path planning task

README.md

@@ -136,4 +136,42 @@ class TaskConfig(GenerationConfig):
     difficulty: str = Field(default="medium", description="easy/medium/hard")
 ```
 
-**Single entry point:** `python examples/generate.py --num-samples 50`
+**Single entry point:** `python examples/generate.py --num-samples 50`
+
+---
+
+## 🎯 Available Tasks
+
+### Path Planning Task (避障路径规划)
+
+A visual reasoning task where a path must be found from start to goal avoiding obstacles.
+
+**Task Description:**
+- **Input:** Grid map with black obstacles, red start point, and green goal point
+- **Output:** Same map with a blue path drawn from start to goal, avoiding all obstacles
+
+**Example Prompt:**
+> "Draw a continuous line from the red start circle to the green goal circle, avoiding all black obstacles."
+
+**Usage:**
+```bash
+python examples/generate_path_planning.py --num-samples 10
+python examples/generate_path_planning.py --num-samples 50 --grid-width 20 --grid-height 15
+```
+
+**Configuration Options:**
+| Parameter | Default | Description |
+|-----------|---------|-------------|
+| `grid_width` | 15 | Grid width in cells |
+| `grid_height` | 10 | Grid height in cells |
+| `cell_size` | 40 | Cell size in pixels |
+| `obstacle_density` | 0.25 | Percentage of cells as obstacles (0.0-1.0) |
+
+**Output Structure:**
+```
+data/questions/path_planning_task/{task_id}/
+├── first_frame.png    # Map with obstacles, start, and goal
+├── final_frame.png    # Map with solution path drawn
+├── prompt.txt         # Task instructions
+└── ground_truth.mp4   # Animation of path being drawn
+```

examples/generate_path_planning.py

@@ -0,0 +1,115 @@
+#!/usr/bin/env python3
+"""
+╔══════════════════════════════════════════════════════════════════════════════╗
+║                      PATH PLANNING TASK GENERATION                            ║
+║                                                                               ║
+║  Generate obstacle avoidance path planning task dataset.                      ║
+║  Task: Find path from start to goal avoiding obstacles.                       ║
+╚══════════════════════════════════════════════════════════════════════════════╝
+
+Usage:
+    python examples/generate_path_planning.py --num-samples 10
+    python examples/generate_path_planning.py --num-samples 100 --output data/path --seed 42
+    python examples/generate_path_planning.py --num-samples 50 --grid-width 20 --grid-height 15
+"""
+
+import argparse
+from pathlib import Path
+import sys
+
+# Add project root to path
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from core import OutputWriter
+from src import PathPlanningGenerator, PathPlanningConfig
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="Generate path planning task dataset",
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+        epilog="""
+Examples:
+    python examples/generate_path_planning.py --num-samples 10
+    python examples/generate_path_planning.py --num-samples 100 --output data/path --seed 42
+    python examples/generate_path_planning.py --num-samples 50 --grid-width 20 --grid-height 15
+        """
+    )
+    parser.add_argument(
+        "--num-samples",
+        type=int,
+        required=True,
+        help="Number of task samples to generate"
+    )
+    parser.add_argument(
+        "--output",
+        type=str,
+        default="data/questions",
+        help="Output directory (default: data/questions)"
+    )
+    parser.add_argument(
+        "--seed",
+        type=int,
+        default=None,
+        help="Random seed for reproducibility"
+    )
+    parser.add_argument(
+        "--no-videos",
+        action="store_true",
+        help="Disable video generation"
+    )
+    parser.add_argument(
+        "--grid-width",
+        type=int,
+        default=15,
+        help="Grid width in cells (default: 15)"
+    )
+    parser.add_argument(
+        "--grid-height",
+        type=int,
+        default=10,
+        help="Grid height in cells (default: 10)"
+    )
+    parser.add_argument(
+        "--cell-size",
+        type=int,
+        default=40,
+        help="Cell size in pixels (default: 40)"
+    )
+    parser.add_argument(
+        "--obstacle-density",
+        type=float,
+        default=0.25,
+        help="Obstacle density 0.0-1.0 (default: 0.25)"
+    )
+
+    args = parser.parse_args()
+
+    print(f"🎲 Generating {args.num_samples} path planning tasks...")
+    print(f"   Grid: {args.grid_width}x{args.grid_height}, Obstacle density: {args.obstacle_density}")
+
+    # Configure task
+    config = PathPlanningConfig(
+        num_samples=args.num_samples,
+        random_seed=args.seed,
+        output_dir=Path(args.output),
+        generate_videos=not args.no_videos,
+        grid_width=args.grid_width,
+        grid_height=args.grid_height,
+        cell_size=args.cell_size,
+        obstacle_density=args.obstacle_density,
+    )
+
+    # Generate tasks
+    generator = PathPlanningGenerator(config)
+    tasks = generator.generate_dataset()
+
+    # Write to disk
+    writer = OutputWriter(Path(args.output))
+    writer.write_dataset(tasks)
+
+    print(f"✅ Done! Generated {len(tasks)} tasks in {args.output}/{config.domain}_task/")
+
+
+if __name__ == "__main__":
+    main()

src/__init__.py

@@ -5,10 +5,26 @@
     - config.py   : Task-specific configuration (TaskConfig)
     - generator.py: Task generation logic (TaskGenerator)
     - prompts.py  : Task prompts/instructions (get_prompt)
+    - path_planning_task.py: Path planning task (PathPlanningGenerator)
 """
 
 from .config import TaskConfig
 from .generator import TaskGenerator
 from .prompts import get_prompt
+from .path_planning_task import (
+    PathPlanningConfig,
+    PathPlanningTask,
+    PathPlanningGenerator,
+    get_path_planning_prompt
+)
 
-__all__ = ["TaskConfig", "TaskGenerator", "get_prompt"]
+__all__ = [
+    "TaskConfig",
+    "TaskGenerator", 
+    "get_prompt",
+    # Path planning task
+    "PathPlanningConfig",
+    "PathPlanningTask",
+    "PathPlanningGenerator",
+    "get_path_planning_prompt",
+]