modules/mazlib/draw.py

import math
import logging
from PIL import Image, ImageDraw


def draw_maze(maze, path, cell=20, save_path=None, show_doors=False, color_dict={'wall':'black', 'floor':'white', 'start':'green', 'door':'#B0B0B0', 'path':'red'}):
    """
    Draw the maze and an optional path using PIL.

    Args:
        maze (list[list[int]]): 2D grid with 1 for walls and 0 for open cells.
        path (list[tuple[int,int]]): sequence of (x, y) coordinates forming a path through the maze.
        cell (int): pixel size of one maze cell when rendering. Default is 20.
        save_path (str|None): if given, save the rendered image to this file path; if None, show the image instead.
        show_doors (bool): if True, draw thin grey outlines around each cell to indicate doors.
        color_dict (dict): optional dict to specify colors for 'wall', 'floor', 'start', 'door', and 'path'.
    """
    h,w = len(maze),len(maze[0])
    img = Image.new('RGB', (w*cell,h*cell), color_dict.get('floor', 'white'))
    draw = ImageDraw.Draw(img)

    # fill start cell (0,0) with green floor
    draw.rectangle([0, 0, cell, cell], fill=color_dict.get('start', 'green'))
    # Optional thin grey outlines for each cell (like hex show_doors)
    if show_doors:
        for y in range(h):
            for x in range(w):
                draw.rectangle(
                    [x * cell, y * cell, (x + 1) * cell, (y + 1) * cell],
                    outline=color_dict.get('door', '#B0B0B0'),
                    width=1
                )

    # Draw solid walls
    for y in range(h):
        for x in range(w):
            if maze[y][x]:
                draw.rectangle([x*cell,y*cell,(x+1)*cell,(y+1)*cell], fill=color_dict.get('wall', 'black'))

    # Draw 2px exterior border, leaving an opening at the exit cell (w-1, h-1)
    img_w, img_h = w * cell, h * cell
    border_width = 4
    draw.rectangle([0, 0, img_w - 1, img_h - 1], outline=color_dict.get('wall', 'black'), width=border_width)
    ex0, ey0 = (w - 1) * cell, (h - 1) * cell
    draw.line([(img_w - 1, ey0), (img_w - 1, ey0 + cell)], fill=color_dict.get('door', '#B0B0B0'), width=border_width + 2)
    draw.line([(ex0, img_h - 1), (ex0 + cell, img_h - 1)], fill=color_dict.get('door', '#B0B0B0'), width=border_width + 2)

    if path:
        for i in range(len(path)-1):
            x1,y1 = path[i]; x2,y2 = path[i+1]
            draw.line([(x1*cell+cell//2,y1*cell+cell//2),(x2*cell+cell//2,y2*cell+cell//2)], fill=color_dict.get('path', 'red'), width=3)
    if save_path:
        try:
            img.save(save_path)
            logging.info("Saved rectangular maze image to %s", save_path)
        except Exception:
            logging.exception("Failed to save image to %s", save_path)
    return img


def draw_hex_maze(maze, path, cell_size=45, rotation_degrees=0, save_path=None, show_doors=False, color_dict={'wall':'black', 'floor':'white', 'start':'green', 'door':'#B0B0B0', 'path':'red'}):
    """
    Draw a hex maze (walls only where no passage) and optional path using PIL.

    Args:
        maze (dict): mapping (q, r) -> list of (dq, dr) neighbor offsets.
        path (list[tuple[int,int]]): sequence of axial coordinates to draw as red line.
        cell_size (int): approximate pixel size of a hex cell.
        save_path (str|None): if given, save image to file instead of showing.
        rotation_degrees (float): rotation of hexagons in degrees (default 0 = flat-topped).
        save_path (str|None): if provided, save the rendered image to this path; if None, show the image.
        show_doors (bool): if True, draw thin grey outlines around each hex to show doors.
        color_dict (dict): optional dict to specify colors for 'wall', 'floor', 'start', and 'door'.
    """
    rot = math.radians(rotation_degrees)
    if not maze: return
    r_max = max((max(abs(q),abs(r)) for q,r in maze), default=5)
    w = int(3*(r_max+2)*cell_size)
    h = int(math.sqrt(3)*2*(r_max+2)*cell_size)
    img = Image.new('RGB', (w,h), color_dict.get('floor', 'white'))
    d = ImageDraw.Draw(img)
    dirs = [(1,0),(0,1),(-1,1),(-1,0),(0,-1),(1,-1)]

    if show_doors:
        for q,r in maze:  # light grey outlines
            cx = cell_size*1.5*q + w//2
            cy = cell_size*math.sqrt(3)*(r + q/2) + h//2
            pts = [(cx + cell_size*math.cos(rot + i*math.pi/3),
                    cy + cell_size*math.sin(rot + i*math.pi/3)) for i in range(6)]
            d.polygon(pts, outline=color_dict.get('door', '#B0B0B0'), width=2)
    # fill start hex (0,0) with green floor so the starting cell is visibly marked
    if (0, 0) in maze:
        cx = w//2
        cy = h//2
        start_pts = [(cx + cell_size*math.cos(rot + i*math.pi/3),
                      cy + cell_size*math.sin(rot + i*math.pi/3)) for i in range(6)]
        d.polygon(start_pts, fill=color_dict.get('start', 'green'))

    for q,r in maze:  # black blocked walls
        cx = cell_size*1.5*q + w//2
        cy = cell_size*math.sqrt(3)*(r + q/2) + h//2
        for i,(dq,dr) in enumerate(dirs):
            if (dq,dr) not in maze.get((q,r),[]):
                a = rot + i*math.pi/3
                x1 = cx + cell_size*math.cos(a)
                y1 = cy + cell_size*math.sin(a)
                x2 = cx + cell_size*math.cos(a+math.pi/3)
                y2 = cy + cell_size*math.sin(a+math.pi/3)
                d.line([(x1,y1),(x2,y2)], fill=color_dict.get('wall', 'black'), width=6)

    # force clear exit to outside on end cell (outer side with no neighbor)
    end = max(maze, key=lambda p: abs(p[0])+abs(p[1])+abs(p[0]+p[1]))
    cx = cell_size*1.5*end[0] + w//2
    cy = cell_size*math.sqrt(3)*(end[1] + end[0]/2) + h//2
    for i,(dq,dr) in enumerate(dirs):
        neigh = (end[0]+dq, end[1]+dr)
        if neigh not in maze:  # outer side
            a = rot + i*math.pi/3
            x1 = cx + cell_size*math.cos(a)
            y1 = cy + cell_size*math.sin(a)
            x2 = cx + cell_size*math.cos(a+math.pi/3)
            y2 = cy + cell_size*math.sin(a+math.pi/3)
            d.line([(x1,y1),(x2,y2)], fill=color_dict.get('floor', 'white'), width=26)
            break

    if path:
        pts = [(cell_size*1.5*q + w//2, cell_size*math.sqrt(3)*(r + q/2) + h//2) for q,r in path]
        d.line(pts, fill=color_dict.get('path', 'red'), width=7)

    if save_path:
        try:
            img.save(save_path)
            logging.info("Saved hex maze image to %s", save_path)
        except Exception:
            logging.exception("Failed to save image to %s", save_path)
    return img


def draw_tri_maze(maze, path, cell=40, save_path=None, show_doors=False, color_dict={'wall':'black', 'floor':'white', 'start':'green', 'door':'#B0B0B0', 'path':'red'}):
    """
    Draw a triangular-grid maze using PIL.

    Maze format expected:
        maze (dict): mapping (x, y) -> list of (dx, dy) neighbor offsets that are open.
    Each cell is an equilateral triangle. Coordinates are grid indices (x:col, y:row).

    Args:
        maze (dict): triangle adjacency mapping.
        path (list[tuple[int,int]]): list of (x,y) cells forming a path.
        cell (int): side length of each triangle in pixels.
        save_path (str|None): save to file if provided, otherwise show.
        show_doors (bool): if True draw thin grey outlines around each triangle.
        color_dict (dict): optional dict to specify colors for 'wall', 'floor', 'start', 'door', and 'path'.
    """
    if not maze:
        return
    # determine bounds
    xs = [p[0] for p in maze]
    ys = [p[1] for p in maze]
    min_x, max_x = min(xs), max(xs)
    min_y, max_y = min(ys), max(ys)
    w = max_x - min_x + 1
    h = max_y - min_y + 1

    side = cell
    h_tri = side * math.sqrt(3) / 2.0
    offset_x = side  # margin
    offset_y = side

    img_w = int(offset_x*2 + (w-1) * (side/2.0) + side + 0.5)
    img_h = int(offset_y*2 + h * h_tri + 0.5)
    img = Image.new('RGB', (img_w, img_h), color_dict.get('floor', 'white'))
    d = ImageDraw.Draw(img)

    def cell_vertices(x,y):
        cx = offset_x + (x - min_x) * (side/2.0)
        cy = offset_y + (y - min_y) * h_tri
        up = ((x + y) % 2 == 0)
        if up:
            v0 = (cx, cy)
            v1 = (cx - side/2.0, cy + h_tri)
            v2 = (cx + side/2.0, cy + h_tri)
        else:
            v0 = (cx, cy + h_tri)
            v1 = (cx - side/2.0, cy)
            v2 = (cx + side/2.0, cy)
        return up, v0, v1, v2

    # fill start triangle (0,0) with green floor so the starting cell is visibly marked
    if (0, 0) in maze:
        _, v0_0, v1_0, v2_0 = cell_vertices(0, 0)
        d.polygon([v0_0, v1_0, v2_0], fill=color_dict.get('start', 'green'))

    # optional thin grey outlines for each triangle
    if show_doors:
        for (x,y) in maze:
            up, v0, v1, v2 = cell_vertices(x,y)
            pts = [v0, v1, v2]
            d.polygon(pts, outline=color_dict.get('door', '#B0B0B0'), width=1)

    # draw black walls where no passage
    for (x,y) in maze:
        up, v0, v1, v2 = cell_vertices(x,y)
        # map direction offsets to edge vertex pairs
        if up:
            edge_map = {
                (-1,0): (v0, v1),  # left
                (1,0): (v0, v2),   # right
                (0,1): (v1, v2),   # down/base
            }
        else:
            edge_map = {
                (-1,0): (v1, v0),  # left
                (1,0): (v2, v0),   # right
                (0,-1): (v1, v2),  # up/base
            }
        for off,verts in edge_map.items():
            if off not in maze.get((x,y), []):
                d.line([verts[0], verts[1]], fill=color_dict.get('wall', 'black'), width=6)

    # force clear exit on end cell (outer side with no neighbor)
    # choose end as max by x+y
    end = max(maze, key=lambda p: p[0] + p[1])
    ex, ey = end
    up, v0, v1, v2 = cell_vertices(ex, ey)
    if up:
        dir_order = [(-1,0),(1,0),(0,1)]
        edge_order = [(v0,v1),(v0,v2),(v1,v2)]
    else:
        dir_order = [(-1,0),(1,0),(0,-1)]
        edge_order = [(v1,v0),(v2,v0),(v1,v2)]
    for off,edge in zip(dir_order, edge_order):
        neigh = (ex + off[0], ey + off[1])
        if neigh not in maze:
            d.line([edge[0], edge[1]], fill=color_dict.get('floor', 'white'), width=26)
            break

    # draw path if provided (connect centroids)
    if path:
        pts = []
        for x,y in path:
            up, v0, v1, v2 = cell_vertices(x,y)
            # centroid average of vertices
            cx = (v0[0] + v1[0] + v2[0]) / 3.0
            cy = (v0[1] + v1[1] + v2[1]) / 3.0
            pts.append((cx, cy))
        d.line(pts, fill=color_dict.get('path', 'red'), width=7)

    if save_path:
        try:
            img.save(save_path)
            logging.info("Saved triangular maze image to %s", save_path)
        except Exception:
            logging.exception("Failed to save tri image to %s", save_path)
    return img