Complete Roguelike Tutorial, using python+libtcod

Hi there! This is a work-in-progress collab effort by a small group of developers to create a Python/libtcod tutorial. As you probably guessed, there isn't much to look at right now, for the casual reader, but there will when the whole thing is completed!

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Title: My First RL!

A general framework / guideline for the tutorial follows. It's already broken out into a few sections, with a small description for each, but it's by no means set in stone.

Some code for the first parts is available at the end.

Graphics

Single torch, fog-of-war (so it feels like you're actually exploring)

Levels

BSP generated dungeons so we can just use what libtcod already has. Town level and shop a bit too much?

The code includes a simple algorithm, it's just a sequence of rooms, each one connected to the next through a tunnel. The overlaps make it look more complex than may be apparent at first though.

Stats

HP/Attack/Defense, for both the player and every monster. (I'm sure this is one of those areas where a beginner would love to tinker and it's pretty easy to add other stats.)

Items

Additive HP/Attack/Defense modifiers when worn. A string determines its class. Can equip one item of every class (weapon, armor, helmet...). Item screen with drop and use options (use equips/dequips stuff). (Should be relatively easy in python at least, where list support is awesome.)

Combat

Damage = Attack - Defense, or something. Would be cool to have a special graphical effect tied to wands and staffs (which would just be weapons with different names).

AI

Cast ray to player, if unblocked move towards, if near it, attack.

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Following is the code I (Jotaf) came up with, for the above first two parts. Since the first part shouldn't know anything about map generation, it could be replaced by a fixed map, like in the libtcod demo. It's ready to run, give it a try! Put libtcod in the same folder if it's not added to your python installation, and place the font 'celtic_garamond_10x10_gs_tc.png' there. (Or change the code to use another one.)

#!/usr/bin/python
#
# libtcod python tutorial
#

import libtcodpy as libtcod

# Import Psyco if available
try:
    import psyco
    psyco.full()
except ImportError:
    pass

#actual size of the window
SCREEN_WIDTH = 80
SCREEN_HEIGHT = 50

#size of the map
MAP_WIDTH = 80
MAP_HEIGHT = 45

#parameters for dungeon generator
ROOM_MAX_SIZE = 10
ROOM_MIN_SIZE = 6
MAX_ROOMS = 30

TORCH_RADIUS = 10
SQUARED_TORCH_RADIUS = TORCH_RADIUS * TORCH_RADIUS

FOV_ALGO = 0  #default FOV algorithm
FOV_LIGHT_WALLS = True  #light walls or not

LIMIT_FPS = 20  #20 frames-per-second maximum


fov_dark_wall = libtcod.Color(0, 0, 100)
fov_light_wall = libtcod.Color(130, 110, 50)
fov_dark_ground = libtcod.Color(50, 50, 150)
fov_light_ground = libtcod.Color(200, 180, 50)


class Tile:
    #a tile of the map and its properties
    def __init__(self, blocked, block_sight = None):
        self.blocked = blocked
        
        #all tiles start unexplored
        self.explored = False
        
        #by default, if a tile is blocked, it also blocks sight
        if block_sight is None: block_sight = blocked
        self.block_sight = block_sight

class Rect:
    #a rectangle on the map. used to characterize a room.
    def __init__(self, x, y, w, h):
        self.x1 = x
        self.y1 = y
        self.x2 = x + w
        self.y2 = y + h
    
    def center(self):
        center_x = (self.x1 + self.x2) / 2
        center_y = (self.y1 + self.y2) / 2
        return (center_x, center_y)
    
    def intersect(self, other):
        #returns true if this rectangle intersects with another one
        return (self.x1 <= other.x2 and self.x2 >= other.x1 and
                self.y1 <= other.y2 and self.y2 >= other.y1)

class Object:
    #this is a generic object: the player, a monster, an item, the stairs...
    #it's always represented by a character on screen.
    def __init__(self, x, y, char, color):
        self.x = x
        self.y = y
        self.char = char
        self.color = color
    
    def move(self, dx, dy):
        #move by the given amount, if the destination is not blocked
        if not map[self.y + dy][self.x + dx].blocked:
            self.x += dx
            self.y += dy
    
    def draw(self):
        #only show if it's visible to the player
        if libtcod.map_is_in_fov(fov_map, self.x, self.y):
            #set the color and then draw the character that represents this object at its position
            libtcod.console_set_foreground_color(console, self.color)
            libtcod.console_put_char(console, self.x, self.y, self.char, libtcod.BKGND_NONE)
    
    def clear(self):
        #erase the character that represents this object
        libtcod.console_put_char(console, self.x, self.y, ' ', libtcod.BKGND_NONE)



def create_room(room):
    global map
    #go through the tiles in the rectangle and make them passable
    for x in range(room.x1 + 1, room.x2):
        for y in range(room.y1 + 1, room.y2):
            map[y][x].blocked = False
            map[y][x].block_sight = False

def create_h_tunnel(x1, x2, y):
    global map
    #horizontal tunnel. min() and max() are used in case x1>x2
    for x in range(min(x1, x2), max(x1, x2) + 1):
        map[y][x].blocked = False
        map[y][x].block_sight = False

def create_v_tunnel(y1, y2, x):
    global map
    #vertical tunnel
    for y in range(min(y1, y2), max(y1, y2) + 1):
        map[y][x].blocked = False
        map[y][x].block_sight = False

def make_map():
    global map, player, stairs
    
    #fill map with "blocked" tiles
    map = [[ Tile(True)
        for x in range(MAP_WIDTH) ]
            for y in range(MAP_HEIGHT) ]

    rooms = []
    num_rooms = 0
    
    for r in range(MAX_ROOMS):
        #random width and height
        w = libtcod.random_get_int(0, ROOM_MIN_SIZE, ROOM_MAX_SIZE)
        h = libtcod.random_get_int(0, ROOM_MIN_SIZE, ROOM_MAX_SIZE)
        #random position without going out of the boundaries of the map
        x = libtcod.random_get_int(0, 0, MAP_WIDTH - w - 1)
        y = libtcod.random_get_int(0, 0, MAP_HEIGHT - h - 1)
        
        #"Rect" class makes rectangles easier to work with
        new_room = Rect(x, y, w, h)
        
        #run through the other rooms and see if they intersect with this one
        failed = False
        for other_room in rooms:
            if new_room.intersect(other_room):
                failed = True
                continue
        
        if not failed:
            #this means there are no intersections, so this room is valid
            
            #"paint" it to the map's tiles
            create_room(new_room)
            
            #center coordinates of new room, will be useful later
            (new_x, new_y) = new_room.center()
            
            if num_rooms == 0:
                #this is the first room, where the player starts at
                player.x = new_x
                player.y = new_y
            else:
                #all rooms after the first:
                #connect it to the previous room with a tunnel
                
                #center coordinates of previous room
                (prev_x, prev_y) = rooms[num_rooms-1].center()
                
                #draw a coin (random number that is either 0 or 1)
                if libtcod.random_get_int(0, 0, 1) == 1:
                    #first move horizontally, then vertically
                    create_h_tunnel(prev_x, new_x, prev_y)
                    create_v_tunnel(prev_y, new_y, new_x)
                else:
                    #first move vertically, then horizontally
                    create_v_tunnel(prev_y, new_y, prev_x)
                    create_h_tunnel(prev_x, new_x, new_y)
            
            #finally, append the new room to the list
            rooms.append(new_room)
            num_rooms += 1
    
    #after that, place the stairs at the last room
    stairs.x = new_x
    stairs.y = new_y


def render_all(key):
    global fov_map, fov_dark_wall, fov_light_wall
    global fov_dark_ground, fov_light_ground
    global fov_recompute

    #draw all objects in the list
    for object in objects:
        object.draw()
    
    if fov_recompute:
        #recompute FOV if needed (the player moved or something)
        fov_recompute = False
        libtcod.map_compute_fov(fov_map, player.x, player.y, TORCH_RADIUS, FOV_LIGHT_WALLS, FOV_ALGO)

        #go through all tiles, and set their background color according to the FOV
        for y in range(MAP_HEIGHT):
            for x in range(MAP_WIDTH):
                visible = libtcod.map_is_in_fov(fov_map, x, y)
                wall = map[y][x].block_sight
                if not visible:
                    #if it's not visible right now, the player can only see it if it's explored
                    if map[y][x].explored:
                        if wall:
                            libtcod.console_set_back(console, x, y, fov_dark_wall, libtcod.BKGND_SET)
                        else:
                            libtcod.console_set_back(console, x, y, fov_dark_ground, libtcod.BKGND_SET)
                else:
                    #it's visible
                    if wall:
                        libtcod.console_set_back(console, x, y, fov_light_wall, libtcod.BKGND_SET )
                    else:
                        libtcod.console_set_back(console, x, y, fov_light_ground, libtcod.BKGND_SET )
                    #since it's visible, explore it
                    map[y][x].explored = True
    
def handle_key(key):
    global fov_recompute
    
    if key.vk == libtcod.KEY_ENTER and key.lalt:
        #Alt+Enter: toggle fullscreen
        libtcod.console_set_fullscreen(not libtcod.console_is_fullscreen())
        
    elif key.vk == libtcod.KEY_ESCAPE:
        return True  #exit game
    
    #movement keys
    elif libtcod.console_is_key_pressed(libtcod.KEY_UP):
        player.move(0, -1)
        fov_recompute = True
        
    elif libtcod.console_is_key_pressed(libtcod.KEY_DOWN):
        player.move(0, 1)
        fov_recompute = True
        
    elif libtcod.console_is_key_pressed(libtcod.KEY_LEFT):
        player.move(-1, 0)
        fov_recompute = True
        
    elif libtcod.console_is_key_pressed(libtcod.KEY_RIGHT):
        player.move(1, 0)
        fov_recompute = True


#############################################
# Initialization & Main Loop
#############################################

libtcod.console_set_custom_font('celtic_garamond_10x10_gs_tc.png', libtcod.FONT_TYPE_GREYSCALE | libtcod.FONT_LAYOUT_TCOD)
libtcod.console_init_root(SCREEN_WIDTH, SCREEN_HEIGHT, 'python/libtcod tutorial', False)
console = libtcod.console_new(SCREEN_WIDTH, SCREEN_HEIGHT)
libtcod.sys_set_fps(LIMIT_FPS)

#create object representing the player (location doesn't matter, make_map will set it appropriately)
player = Object(0, 0, '@', libtcod.black)

#create object representing the stairs
stairs = Object(0, 0, '<', libtcod.white)

#the list of objects with those two
objects = [player, stairs]

#generate map (at this point it's not drawn to the screen)
make_map()

#create the FOV map, according to the generated map
fov_map = libtcod.map_new(MAP_WIDTH, MAP_HEIGHT)
for y in range(MAP_HEIGHT):
    for x in range(MAP_WIDTH):
        libtcod.map_set_properties(fov_map, x, y, not map[y][x].blocked, not map[y][x].block_sight) 

#start with a blank console
libtcod.console_clear(console)


fov_recompute = True
credits_end = False

while not libtcod.console_is_window_closed():

    #erase all objects at their old locations, before they move
    for object in objects:
        object.clear()

    #handle keys and exit game if needed
    key = libtcod.console_check_for_keypress()
    exit = handle_key(key)
    if exit:
        break
    
    #render the screen
    render_all(key)
    libtcod.console_blit(console,
                        0, 0, MAP_WIDTH, MAP_HEIGHT,
                        0, 0, 0, 255)
    
    # render credits at the bottom
    if not credits_end: 
        credits_end = libtcod.console_credits_render(0, MAP_HEIGHT, 0)

    # render stats
    libtcod.console_set_foreground_color(None, libtcod.grey)
    libtcod.console_print_right(None, 79, 46, libtcod.BKGND_NONE, 
                                'last frame : %3d ms (%3d fps)' %
                                (int(libtcod.sys_get_last_frame_length() * 
                                    1000.0), libtcod.sys_get_fps()))
    libtcod.console_print_right(None, 79, 47, libtcod.BKGND_NONE, 
                                'elapsed : %8d ms %4.2fs' %
                                (libtcod.sys_elapsed_milli(), 
                                libtcod.sys_elapsed_seconds()))
    
    
    #victory screen!
    if player.x == stairs.x and player.y == stairs.y:
        libtcod.console_clear(0)
        libtcod.console_set_foreground_color(None, libtcod.white)
        libtcod.console_print_center(None, SCREEN_WIDTH/2, SCREEN_HEIGHT/2, libtcod.BKGND_NONE, 
                                'Victory is Yours!!')
    
    libtcod.console_flush()