AStarPath

Computed A* path result, consumed step by step.

Overview

An AStarPath represents a computed shortest path between two points on a Grid. It is created by Grid.find_path() and cannot be instantiated directly. The path is consumed incrementally using walk() or inspected using peek().

Quick Reference

# Create path from grid
path = grid.find_path((player.x, player.y), (target_x, target_y))

if path:
    # Check path length
    print(f"Path has {path.remaining} steps")

    # Peek at next step without consuming
    next_pos = path.peek()

    # Walk the path step by step
    while path.remaining > 0:
        next_step = path.walk()
        if next_step:
            x, y = next_step
            player.x, player.y = x, y

Constructor

AStarPath cannot be instantiated directly. Use Grid.find_path() to create paths.

# Correct way to create a path
path = grid.find_path(start_pos, end_pos)

Properties

Property	Type	Description
`origin`	tuple	Starting position (x, y), read-only
`destination`	tuple	Target position (x, y), read-only
`remaining`	int	Number of steps remaining, read-only

Methods

Method	Description
`walk()`	Return and consume the next step, or None if exhausted
`peek()`	Return the next step without consuming it

Usage Patterns

Basic Movement

path = grid.find_path(entity.pos, goal)
if path:
    next_step = path.walk()
    if next_step:
        entity.x, entity.y = next_step

Animated Movement

path = grid.find_path(player.pos, target)

def move_step(timer):
    if path.remaining > 0:
        x, y = path.walk()
        player.animate("x", x, duration=0.15)
        player.animate("y", y, duration=0.15)
    else:
        timer.cancel()

mcrfpy.Timer("move", move_step, 200)  # Move every 200ms

Path Validation

path = grid.find_path(start, end)

if path is None:
    print("No path exists!")
elif path.remaining == 0:
    print("Already at destination")
else:
    print(f"Path found: {path.remaining} steps from {path.origin} to {path.destination}")