Source

pygame-tutorial / tmx.py

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Richard Jones 0d75475 
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Richard Jones 305e4af 

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Richard Jones 89cc1f4 









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Richard Jones 0d75475 
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Richard Jones 89cc1f4 



Richard Jones e437d54 
Richard Jones 89cc1f4 






Richard Jones 305e4af 
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Richard Jones c6a598f 
















Richard Jones 89cc1f4 



Richard Jones f1dc8ad 
Richard Jones 305e4af 



Richard Jones f1dc8ad 
Richard Jones c6a598f 
Richard Jones 7e2b9e2 
Richard Jones 89cc1f4 

Richard Jones c6a598f 
Richard Jones 7e2b9e2 
Richard Jones c6a598f 
Richard Jones 234ec84 
Richard Jones c6a598f 
Richard Jones 7e2b9e2 
Richard Jones c6a598f 







Richard Jones 7e2b9e2 
Richard Jones c6a598f 
Richard Jones e437d54 
Richard Jones c6a598f 


Richard Jones e437d54 




Richard Jones 89cc1f4 
Richard Jones f1dc8ad 
















Richard Jones 89cc1f4 
Richard Jones 0d75475 

















Richard Jones 89cc1f4 


Richard Jones f1dc8ad 
Richard Jones 7e2b9e2 
Richard Jones 89cc1f4 








Richard Jones f1dc8ad 



Richard Jones 0d75475 


Richard Jones 89cc1f4 
Richard Jones f1dc8ad 








Richard Jones 7e2b9e2 











Richard Jones 89cc1f4 

Richard Jones 7e2b9e2 





Richard Jones 89cc1f4 
Richard Jones fff32e4 
Richard Jones d66c8a8 

Richard Jones 604f2f9 




Richard Jones e437d54 
Richard Jones 604f2f9 
Richard Jones 0d75475 


Richard Jones e437d54 
Richard Jones 604f2f9 
Richard Jones 17bc75a 
Richard Jones 89cc1f4 
Richard Jones 17bc75a 
Richard Jones 89cc1f4 


Richard Jones 17bc75a 
Richard Jones 0d75475 
Richard Jones 89cc1f4 
Richard Jones 91afdce 





Richard Jones f1dc8ad 
Richard Jones 91afdce 




Richard Jones e437d54 
Richard Jones 89cc1f4 
Richard Jones e437d54 
Richard Jones 89cc1f4 
Richard Jones c6a598f 
Richard Jones 89cc1f4 
Richard Jones c6a598f 
Richard Jones 89cc1f4 


Richard Jones e437d54 


Richard Jones 305e4af 


Richard Jones e437d54 

Richard Jones 7e2b9e2 
Richard Jones e437d54 
Richard Jones 305e4af 












Richard Jones e437d54 
Richard Jones 305e4af 

Richard Jones e437d54 
Richard Jones 305e4af 
Richard Jones f1dc8ad 


























Richard Jones ef9e81b 
Richard Jones 305e4af 
Richard Jones ef9e81b 
Richard Jones 305e4af 






Richard Jones 17bc75a 
Richard Jones 305e4af 
Richard Jones ef9e81b 
Richard Jones 17bc75a 
Richard Jones 305e4af 
Richard Jones ef9e81b 
Richard Jones 305e4af 
Richard Jones 17bc75a 
Richard Jones 305e4af 
Richard Jones 91afdce 












Richard Jones 7e2b9e2 
Richard Jones 0d75475 

























Richard Jones 604f2f9 
Richard Jones 89cc1f4 






Richard Jones 91afdce 
Richard Jones 89cc1f4 
Richard Jones 604f2f9 


Richard Jones 7e2b9e2 
Richard Jones 89cc1f4 
Richard Jones fff32e4 
Richard Jones d66c8a8 
Richard Jones fff32e4 
Richard Jones d66c8a8 
Richard Jones ef9e81b 
Richard Jones 89cc1f4 

Richard Jones ef9e81b 
Richard Jones 89cc1f4 
Richard Jones 7e2b9e2 


Richard Jones 0d75475 
Richard Jones 7e2b9e2 
Richard Jones 89cc1f4 
Richard Jones 7e2b9e2 






Richard Jones 89cc1f4 
Richard Jones 7e2b9e2 

Richard Jones 89cc1f4 
Richard Jones 7e2b9e2 


Richard Jones 89cc1f4 
Richard Jones 7e2b9e2 
Richard Jones 89cc1f4 
Richard Jones 604f2f9 

























Richard Jones e437d54 

Richard Jones 604f2f9 
Richard Jones e437d54 
Richard Jones 604f2f9 
Richard Jones e437d54 



Richard Jones 604f2f9 

Richard Jones e437d54 

Richard Jones 604f2f9 
Richard Jones e437d54 
Richard Jones 604f2f9 
Richard Jones e437d54 



Richard Jones 604f2f9 








Richard Jones 7e2b9e2 

Richard Jones 604f2f9 
Richard Jones e437d54 


Richard Jones 604f2f9 
Richard Jones e437d54 
Richard Jones 604f2f9 

















Richard Jones 7e2b9e2 
Richard Jones 604f2f9 
Richard Jones 7e2b9e2 

Richard Jones 604f2f9 
Richard Jones 17bc75a 

Richard Jones 604f2f9 

Richard Jones 17bc75a 
Richard Jones 604f2f9 













Richard Jones f1dc8ad 





Richard Jones 305e4af 
Richard Jones 7e2b9e2 
Richard Jones 305e4af 
Richard Jones 7e2b9e2 



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# "Tiled" TMX loader/renderer and more
# Copyright 2012 Richard Jones <richard@mechanicalcat.net>
# This code is placed in the Public Domain.

# TODO: support properties on more things

import sys
import struct
import collections
import pygame
from pygame.locals import *
from pygame import Rect
from xml.etree import ElementTree

class Tile(object):
    def __init__(self, gid, surface, tileset):
        self.gid = gid
        self.surface = surface
        self.tile_width = tileset.tile_width
        self.tile_height = tileset.tile_height
        self.properties = {}

    @classmethod
    def fromSurface(cls, surface):
        '''Create a new Tile object straight from a pygame Surface.

        Its tile_width and tile_height will be set using the Surface dimensions.
        Its gid will be 0.
        '''
        class ts:
            tile_width, tile_height = surface.get_size()
        return cls(0, surface, ts)

    def loadxml(self, tag):
        props = tag.find('properties')
        if props is None:
            return
        for c in props.findall('property'):
            # store additional properties.
            name = c.attrib['name']
            value = c.attrib['value']

            # TODO hax
            if value.isdigit():
                value = int(value)
            self.properties[name] = value

    def __repr__(self):
        return '<Tile %d>' % self.gid

class Tileset(object):
    def __init__(self, name, tile_width, tile_height, firstgid):
        self.name = name
        self.tile_width = tile_width
        self.tile_height = tile_height
        self.firstgid = firstgid
        self.tiles = []
        self.properties = {}

    @classmethod
    def fromxml(cls, tag, firstgid=None):
        if 'source' in tag.attrib:
            firstgid = int(tag.attrib['firstgid'])
            with open(tag.attrib['source']) as f:
                tileset = ElementTree.fromstring(f.read())
            return cls.fromxml(tileset, firstgid)

        name = tag.attrib['name']
        if firstgid is None:
            firstgid = int(tag.attrib['firstgid'])
        tile_width = int(tag.attrib['tilewidth'])
        tile_height = int(tag.attrib['tileheight'])

        tileset = cls(name, tile_width, tile_height, firstgid)

        for c in tag.getchildren():
            if c.tag == "image":
                # create a tileset
                tileset.add_image(c.attrib['source'])
            elif c.tag == 'tile':
                gid = tileset.firstgid + int(c.attrib['id'])
                tileset.get_tile(gid).loadxml(c)
        return tileset

    def add_image(self, file):
        image = pygame.image.load(file).convert_alpha()
        if not image:
            sys.exit("Error creating new Tileset: file %s not found" % file)
        id = self.firstgid
        for line in xrange(image.get_height()/self.tile_height):
            for column in xrange(image.get_width()/self.tile_width):
                pos = Rect(column*self.tile_width,
                    line*self.tile_height,
                    self.tile_width,
                    self.tile_height )
                self.tiles.append(Tile(id, image.subsurface(pos), self))
                id += 1

    def get_tile(self, gid):
        return self.tiles[gid - self.firstgid]

class Tilesets(dict):
    def add(self, tileset):
        for i, tile in enumerate(tileset.tiles):
            i += tileset.firstgid
            self[i] = tile

class Cell(object):
    '''Layers are made of Cells (or empty space).

    Cells have some basic properties:

    x, y - the cell's index in the layer
    px, py - the cell's pixel position
    left, right, top, bottom - the cell's pixel boundaries

    Additionally the cell may have other properties which are accessed using
    standard dictionary methods:

       cell['property name']

    You may assign a new value for a property to or even delete an existing
    property from the cell - this will not affect the Tile or any other Cells
    using the Cell's Tile.
    '''
    def __init__(self, x, y, px, py, tile):
        self.x, self.y = x, y
        self.px, self.py = px, py
        self.tile = tile
        self.topleft = (px, py)
        self.left = px
        self.right = px + tile.tile_width
        self.top = py
        self.bottom = py + tile.tile_height
        self.center = (px + tile.tile_width//2, py + tile.tile_height//2)
        self._added_properties = {}
        self._deleted_properties = set()
    def __repr__(self):
        return '<Cell %s,%s %d>' % (self.px, self.py, self.tile.gid)
    def __contains__(self, key):
        if key in self._deleted_properties:
            return False
        return key in self._added_properties or key in self.tile.properties
    def __getitem__(self, key):
        if key in self._deleted_properties:
            raise KeyError(key)
        if key in self._added_properties:
            return self._added_properties[key]
        if key in self.tile.properties:
            return self.tile.properties[key]
        raise KeyError(key)
    def __setitem__(self, key, value):
        self._added_properties[key] = value
    def __delitem__(self, key):
        self._deleted_properties.add(key)
    def intersects(self, other):
        '''Determine whether this Cell intersects with the other rect (which has
        .x, .y, .width and .height attributes.)
        '''
        if self.px + self.tile.tile_width < other.x: return False
        if other.x + other.width < self.px: return False
        if self.py + self.tile.tile_height < other.y: return False
        if other.y + other.height < self.py: return False
        return True

class LayerIterator(object):
    '''Iterates over all the cells in a layer in column,row order.
    '''
    def __init__(self, layer):
        self.layer = layer
        self.i, self.j = 0, 0
    def next(self):
        if self.i == self.layer.width - 1:
            self.j += 1
            self.i = 0
        if self.j == self.layer.height - 1:
            raise StopIteration()
        value = self.layer[self.i, self.j]
        self.i += 1
        return value


class Layer(object):
    '''A 2d grid of Cells.

    Layers have some basic properties:

        width, height - the dimensions of the Layer in cells
        tile_width, tile_height - the dimensions of each cell
        px_width, px_height - the dimensions of the Layer in pixels
        tilesets - the tilesets used in this Layer (a Tilesets instance)
        properties - any properties set for this Layer
        cells - a dict of all the Cell instances for this Layer, keyed off
                (x, y) index.

    Additionally you may look up a cell using direct item access:

       layer[x, y] is layer.cells[x, y]

    Note that empty cells will be set to None instead of a Cell instance.
    '''
    def __init__(self, name, visible, map):
        self.name = name
        self.visible = visible
        self.position = (0, 0)
        # TODO get from TMX?
        self.px_width = map.px_width
        self.px_height = map.px_height
        self.tile_width = map.tile_width
        self.tile_height = map.tile_height
        self.width = map.width
        self.height = map.height
        self.tilesets = map.tilesets
        self.group = pygame.sprite.Group()
        self.properties = {}
        self.cells = {}

    def __repr__(self):
        return '<Layer "%s" at 0x%x>' % (self.name, id(self))

    def __getitem__(self, pos):
        return self.cells.get(pos)

    def __setitem__(self, pos, tile):
        x, y = pos
        px = x * self.tile_width
        py = y * self.tile_width
        self.cells[pos] = Cell(x, y, px, py, tile)

    def __iter__(self):
        return LayerIterator(self)

    @classmethod
    def fromxml(cls, tag, map):
        layer = cls(tag.attrib['name'], int(tag.attrib.get('visible', 1)), map)

        data = tag.find('data')
        if data is None:
            raise ValueError('layer %s does not contain <data>' % layer.name)

        data = data.text.strip()
        data = data.decode('base64').decode('zlib')
        data = struct.unpack('<%di' % (len(data)/4,), data)
        assert len(data) == layer.width * layer.height
        for i, gid in enumerate(data):
            if gid < 1: continue   # not set
            tile = map.tilesets[gid]
            x = i % layer.width
            y = i // layer.width
            layer.cells[x,y] = Cell(x, y, x*map.tile_width, y*map.tile_height, tile)

        return layer

    def update(self, dt, *args):
        pass

    def set_view(self, x, y, w, h, viewport_ox=0, viewport_oy=0):
        self.view_x, self.view_y = x, y
        self.view_w, self.view_h = w, h
        x -= viewport_ox
        y -= viewport_oy
        self.position = (x, y)

    def draw(self, surface):
        '''Draw this layer, limited to the current viewport, to the Surface.
        '''
        ox, oy = self.position
        w, h = self.view_w, self.view_h
        for x in range(ox, ox+w+self.tile_width, self.tile_width):
            i = x // self.tile_width
            for y in range(oy, oy+h+self.tile_height, self.tile_height):
                j = y // self.tile_height
                if (i, j) not in self.cells:
                    continue
                cell = self.cells[i, j]
                surface.blit(cell.tile.surface, (cell.px-ox, cell.py-oy))

    def find(self, *properties):
        '''Find all cells with the given properties set.
        '''
        r = []
        for propname in properties:
            for cell in self.cells.values():
                if cell and propname in cell:
                    r.append(cell)
        return r

    def match(self, **properties):
        '''Find all cells with the given properties set to the given values.
        '''
        r = []
        for propname in properties:
            for cell in self.cells.values():
                if propname not in cell:
                    continue
                if properties[propname] == cell[propname]:
                    r.append(cell)
        return r

    def collide(self, rect, propname):
        '''Find all cells the rect is touching that have the indicated property
        name set.
        '''
        r = []
        for cell in self.get_in_region(rect.left, rect.top, rect.right, rect.bottom):
            if not cell.intersects(rect):
                continue
            if propname in cell:
                r.append(cell)
        return r

    def get_in_region(self, x1, y1, x2, y2):
        '''Return cells (in [column][row]) that are within the map-space
        pixel bounds specified by the bottom-left (x1, y1) and top-right
        (x2, y2) corners.

        Return a list of Cell instances.
        '''
        i1 = max(0, x1 // self.tile_width)
        j1 = max(0, y1 // self.tile_height)
        i2 = min(self.width, x2 // self.tile_width + 1)
        j2 = min(self.height, y2 // self.tile_height + 1)
        return [self.cells[i, j]
            for i in range(int(i1), int(i2))
                for j in range(int(j1), int(j2))
                    if (i, j) in self.cells]

    def get_at(self, x, y):
        '''Return the cell at the nominated (x, y) coordinate.

        Return a Cell instance or None.
        '''
        i = x // self.tile_width
        j = y // self.tile_height
        return self.cells.get((i, j))

    def neighbors(self, index):
        '''Return the indexes of the valid (ie. within the map) cardinal (ie.
        North, South, East, West) neighbors of the nominated cell index.

        Returns a list of 2-tuple indexes.
        '''
        i, j = index
        n = []
        if i < self.width-1:
            n.append((i+1, j))
        if i > 0:
            n.append((i-1, j))
        if j < self.height-1:
            n.append((i, j+1))
        if j > 0:
            n.append((i, j-1))
        return n

class SpriteLayer(pygame.sprite.AbstractGroup):
    def __init__(self):
        super(SpriteLayer, self).__init__()
        self.visible = True

    def set_view(self, x, y, w, h, viewport_ox=0, viewport_oy=0):
        self.view_x, self.view_y = x, y
        self.view_w, self.view_h = w, h
        x -= viewport_ox
        y -= viewport_oy
        self.position = (x, y)

    def draw(self, screen):
        ox, oy = self.position
        w, h = self.view_w, self.view_h
        for sprite in self.sprites():
            sx, sy = sprite.rect.topleft
            screen.blit(sprite.image, (sx-ox, sy-oy))

class Layers(list):
    def __init__(self):
        self.by_name = {}

    def add_named(self, layer, name):
        self.append(layer)
        self.by_name[name] = layer

    def __getitem__(self, item):
        if isinstance(item, int):
            return self[item]
        return self.by_name[item]

class TileMap(object):
    '''A TileMap is a collection of Layers which contain gridded maps or sprites
    which are drawn constrained by a viewport.

    And breathe.

    TileMaps are loaded from TMX files which sets the .layers and .tilesets
    properties. After loading additional SpriteLayers may be added.

    A TileMap's rendering is restricted by a viewport which is defined by the
    size passed in at construction time and the focus set by set_focus() or
    force_focus().

    TileMaps have a number of properties:

        width, height - the dimensions of the tilemap in cells
        tile_width, tile_height - the dimensions of the cells in the map
        px_width, px_height - the dimensions of the tilemap in pixels
        properties - any properties set on the tilemap in the TMX file
        layers - all layers of this tilemap as a Layers instance
        tilesets - all tilesets of this tilemap as a Tilesets instance
        fx, fy - viewport focus point
        view_w, view_h - viewport size
        view_x, view_y - viewport offset (origin)
        viewport - a Rect instance giving the current viewport specification

    '''
    def __init__(self, size, origin=(0,0)):
        self.px_width = 0
        self.px_height = 0
        self.tile_width = 0
        self.tile_height = 0
        self.width = 0
        self.height  = 0
        self.properties = {}
        self.layers = Layers()
        self.tilesets = Tilesets()
        self.fx, self.fy = 0, 0             # viewport focus point
        self.view_w, self.view_h = size     # viewport size
        self.view_x, self.view_y = origin   # viewport offset
        self.viewport = Rect(origin, size)

    def update(self, dt, *args):
        for layer in self.layers:
            layer.update(dt, *args)

    def draw(self, screen):
        for layer in self.layers:
            if layer.visible:
                layer.draw(screen)

    @classmethod
    def load(cls, filename, viewport):
        with open(filename) as f:
            map = ElementTree.fromstring(f.read())

        # get most general map informations and create a surface
        tilemap = TileMap(viewport)
        tilemap.width = int(map.attrib['width'])
        tilemap.height  = int(map.attrib['height'])
        tilemap.tile_width = int(map.attrib['tilewidth'])
        tilemap.tile_height = int(map.attrib['tileheight'])
        tilemap.px_width = tilemap.width * tilemap.tile_width
        tilemap.px_height = tilemap.height * tilemap.tile_height

        for tag in map.findall('tileset'):
            tilemap.tilesets.add(Tileset.fromxml(tag))

        for tag in map.findall('layer'):
            layer = Layer.fromxml(tag, tilemap)
            tilemap.layers.add_named(layer, layer.name)

        return tilemap

    _old_focus = None
    def set_focus(self, fx, fy, force=False):
        '''Determine the viewport based on a desired focus pixel in the
        Layer space (fx, fy) and honoring any bounding restrictions of
        child layers.

        The focus will always be shifted to ensure no child layers display
        out-of-bounds data, as defined by their dimensions px_width and px_height.
        '''
        # The result is that all chilren will have their viewport set, defining
        # which of their pixels should be visible.
        fx, fy = int(fx), int(fy)
        self.fx, self.fy = fx, fy

        a = (fx, fy)

        # check for NOOP (same arg passed in)
        if not force and self._old_focus == a:
            return
        self._old_focus = a

        # get our viewport information, scaled as appropriate
        w = int(self.view_w)
        h = int(self.view_h)
        w2, h2 = w//2, h//2

        if self.px_width <= w:
            # this branch for centered view and no view jump when
            # crossing the center; both when world width <= view width
            restricted_fx = self.px_width / 2
        else:
            if (fx - w2) < 0:
                restricted_fx = w2       # hit minimum X extent
            elif (fx + w2) > self.px_width:
                restricted_fx = self.px_width - w2       # hit maximum X extent
            else:
                restricted_fx = fx
        if self.px_height <= h:
            # this branch for centered view and no view jump when
            # crossing the center; both when world height <= view height
            restricted_fy = self.px_height / 2
        else:
            if (fy - h2) < 0:
                restricted_fy = h2       # hit minimum Y extent
            elif (fy + h2) > self.px_height:
                restricted_fy = self.px_height - h2       # hit maximum Y extent
            else:
                restricted_fy = fy

        # ... and this is our focus point, center of screen
        self.restricted_fx = int(restricted_fx)
        self.restricted_fy = int(restricted_fy)

        # determine child view bounds to match that focus point
        x, y = int(restricted_fx - w2), int(restricted_fy - h2)
        self.viewport.x = x
        self.viewport.y = y

        self.childs_ox = x - self.view_x
        self.childs_oy = y - self.view_y

        for layer in self.layers:
            layer.set_view(x, y, w, h, self.view_x, self.view_y)

    def force_focus(self, fx, fy):
        '''Force the manager to focus on a point, regardless of any managed layer
        visible boundaries.

        '''
        # This calculation takes into account the scaling of this Layer (and
        # therefore also its children).
        # The result is that all chilren will have their viewport set, defining
        # which of their pixels should be visible.
        self.fx, self.fy = map(int, (fx, fy))
        self.fx, self.fy = fx, fy

        # get our view size
        w = int(self.view_w)
        h = int(self.view_h)
        w2, h2 = w//2, h//2

        # bottom-left corner of the viewport
        x, y = fx - w2, fy - h2
        self.viewport.x = x
        self.viewport.y = y

        self.childs_ox = x - self.view_x
        self.childs_oy = y - self.view_y

        for layer in self.layers:
            layer.set_view(x, y, w, h, self.view_x, self.view_y)

    def pixel_from_screen(self, x, y):
        '''Look up the Layer-space pixel matching the screen-space pixel.
        '''
        vx, vy = self.childs_ox, self.childs_oy
        return int(vx + x), int(vy + y)

    def pixel_to_screen(self, x, y):
        '''Look up the screen-space pixel matching the Layer-space pixel.
        '''
        screen_x = x-self.childs_ox
        screen_y = y-self.childs_oy
        return int(screen_x), int(screen_y)

    def index_at(self, x, y):
        '''Return the map index at the (screen-space) pixel position.
        '''
        sx, sy = self.pixel_from_screen(x, y)
        return int(sx//self.tile_width), int(sy//self.tile_height)

def load(filename, viewport):
    return TileMap.load(filename, viewport)

if __name__ == '__main__':
    # allow image load to work
    pygame.init()
    pygame.display.set_mode((640, 480))
    t = load(sys.argv[1], (0, 0))