visualizer.py

import matplotlib
matplotlib.use('Agg')            # no pop-up window
import matplotlib.pyplot as plt
import matplotlib.patches as mpatches
import numpy as np

from grid import FREE, OBSTACLE, START, GOAL

# ── emoji mapping ─────────────────────────────────────────────
EMOJI = {
    FREE:       '⬜',
    OBSTACLE:   '🌳',
    START:      '🚗',
    GOAL:       '🏁',
    'explored': '🟦',
    'path':     '🟨',
}

# ── colour mapping (RGB 0-1) ──────────────────────────────────
COLOR = {
    FREE:       (1.00, 1.00, 1.00),
    OBSTACLE:   (0.25, 0.25, 0.25),
    START:      (0.20, 0.80, 0.20),
    GOAL:       (0.90, 0.20, 0.20),
    'explored': (0.60, 0.80, 1.00),
    'path':     (1.00, 0.85, 0.10),
}


# ── terminal emoji print ──────────────────────────────────────
def print_emoji_grid(grid, explored=(), path=()):
    explored = set(explored)
    path     = set(path)
    for r in range(grid.rows):
        row = ''
        for c in range(grid.cols):
            pos = (r, c)
            if pos == grid.start:
                row += EMOJI[START]
            elif pos == grid.goal:
                row += EMOJI[GOAL]
            elif pos in path:
                row += EMOJI['path']
            elif pos in explored:
                row += EMOJI['explored']
            elif grid.is_obstacle(r, c):
                row += EMOJI[OBSTACLE]
            else:
                row += EMOJI[FREE]
        print(row)
    print()


# ── matplotlib frame renderer ─────────────────────────────────
def render_frame(grid, explored, path, save_path, title='A* Path Planning'):
    explored = set(explored)
    path     = set(path)
    rows, cols = grid.rows, grid.cols

    data = np.ones((rows, cols, 3))
    for r in range(rows):
        for c in range(cols):
            pos = (r, c)
            if pos == grid.start:
                data[r, c] = COLOR[START]
            elif pos == grid.goal:
                data[r, c] = COLOR[GOAL]
            elif pos in path:
                data[r, c] = COLOR['path']
            elif pos in explored:
                data[r, c] = COLOR['explored']
            elif grid.is_obstacle(r, c):
                data[r, c] = COLOR[OBSTACLE]
            # else FREE → already white

    fig, ax = plt.subplots(figsize=(5, 5))
    ax.imshow(data, origin='upper', interpolation='nearest')

    # grid lines
    ax.set_xticks(np.arange(-0.5, cols, 1), minor=True)
    ax.set_yticks(np.arange(-0.5, rows, 1), minor=True)
    ax.grid(which='minor', color='gray', linewidth=0.5)
    ax.tick_params(which='both', bottom=False, left=False,
                   labelbottom=False, labelleft=False)
    ax.set_title(title, fontsize=11)

    # legend
    legend_items = [
        mpatches.Patch(color=COLOR[START],      label='Start'),
        mpatches.Patch(color=COLOR[GOAL],       label='Goal'),
        mpatches.Patch(color=COLOR[OBSTACLE],   label='Obstacle'),
        mpatches.Patch(color=COLOR['explored'], label='Explored'),
        mpatches.Patch(color=COLOR['path'],     label='Path'),
    ]
    ax.legend(handles=legend_items, loc='upper right',
              fontsize=7, framealpha=0.8)

    plt.tight_layout()
    plt.savefig(save_path, dpi=80)
    plt.close(fig)