terom@92: """ terom@92: Rendering output terom@92: """ terom@92: terom@92: import os, os.path terom@92: terom@92: ## Settings terom@92: # width of a tile terom@92: TILE_WIDTH = 256 terom@92: TILE_HEIGHT = 256 terom@92: terom@92: # max. output resolution to allow terom@92: MAX_PIXELS = 1920 * 1200 terom@92: terom@92: def dir_url (prefix, name, item) : terom@92: """ terom@92: Join together an absolute URL prefix, an optional directory name, and a directory item terom@92: """ terom@92: terom@92: url = prefix terom@92: terom@92: if name : terom@92: url += '/' + name terom@92: terom@92: url += '/' + item terom@92: terom@92: return url terom@92: terom@92: def dir_list (dir_path) : terom@92: """ terom@92: Yield a series of directory items to show for the given dir terom@92: """ terom@92: terom@92: # link to parent terom@92: yield '..' terom@92: terom@92: for item in os.listdir(dir_path) : terom@92: path = os.path.join(dir_path, item) terom@92: terom@92: # skip dotfiles terom@92: if item.startswith('.') : terom@92: continue terom@92: terom@92: # show dirs terom@92: if os.path.isdir(path) : terom@92: yield item terom@92: terom@92: # examine ext terom@92: base, ext = os.path.splitext(path) terom@92: terom@92: # show .png files with a .cache file terom@92: if ext == '.png' and os.path.exists(base + '.cache') : terom@92: yield item terom@92: terom@92: terom@92: ### Render HTML data terom@92: def dir_html (prefix, name, path) : terom@92: """ terom@92: Directory index terom@92: """ terom@92: terom@92: name = name.rstrip('/') terom@92: terom@92: return """\ terom@92: terom@92: terom@92: Index of %(dir)s terom@92: terom@92: terom@92: terom@92:

Index of %(dir)s

terom@92: terom@92: terom@92: terom@92: """ % dict( terom@92: prefix = prefix, terom@92: dir = '/' + name, terom@92: terom@92: listing = "\n".join( terom@92: #
  • link terom@92: """
  • %(name)s
    • """ % dict( terom@92: # URL to dir terom@92: url = dir_url(prefix, name, item), terom@92: terom@92: # item name terom@92: name = item, terom@92: ) for item in dir_list(path) terom@92: ), terom@92: ) terom@92: terom@92: def img_html (prefix, name, image) : terom@92: """ terom@92: HTML for image terom@92: """ terom@92: terom@92: # a little slow, but not so bad - two stats(), heh terom@92: info = image.info() terom@92: img_width, img_height = info['img_width'], info['img_height'] terom@92: terom@92: return """\ terom@92: terom@92: terom@92: %(title)s terom@92: terom@92: terom@92: terom@92: terom@92: terom@92: terom@92: terom@92:
    terom@92:
    terom@92:
    terom@92: terom@92: terom@92: terom@92:
    terom@92: terom@92:
    terom@92: terom@92:
    terom@92: Loading... terom@92:
    terom@92:
    terom@92:
    terom@92: terom@92: terom@92: terom@92: """ % dict( terom@92: title = name, terom@92: prefix = prefix, terom@92: tile_url = prefix + '/' + name, terom@92: terom@92: tile_width = TILE_WIDTH, terom@92: tile_height = TILE_HEIGHT, terom@92: terom@92: img_width = img_width, terom@92: img_height = img_height, terom@92: ) terom@92: terom@103: terom@103: # threshold to cache images on - only images with a source data region *larger* than this are cached terom@103: CACHE_THRESHOLD = 512 * 512 terom@103: terom@103: def scale_by_zoom (val, zoom) : terom@103: """ terom@103: Scale dimension by zoom factor terom@127: terom@127: zl > 0 -> bigger terom@127: zl < 0 -> smaller terom@103: """ terom@103: terom@103: if zoom > 0 : terom@103: return val << zoom terom@103: terom@103: elif zoom > 0 : terom@103: return val >> -zoom terom@103: terom@103: else : terom@103: return val terom@103: terom@103: ### Image caching terom@103: def check_cache_threshold (width, height, zl) : terom@103: """ terom@103: Checks if a tile with the given dimensions should be cached terom@103: """ terom@103: terom@127: return (scale_by_zoom(width, zl) * scale_by_zoom(height, zl)) > CACHE_THRESHOLD terom@103: terom@103: def render_raw (image, width, height, x, y, zl) : terom@103: """ terom@103: Render and return tile terom@103: """ terom@103: terom@103: return image.tile_mem( terom@103: width, height, terom@103: x, y, zl terom@103: ) terom@103: terom@103: def render_cache (cache, image, width, height, x, y, zl) : terom@103: """ terom@103: Perform a cached render of the given tile terom@103: """ terom@103: terom@103: if cache : terom@103: # cache key terom@105: key = "tl_%d:%d_%d:%d:%d_%s" % (x, y, width, height, zl, image.path) terom@103: terom@103: # lookup terom@103: data = cache.get(key) terom@103: terom@103: else : terom@103: # oops, no cache terom@103: data = None terom@103: terom@103: if not data : terom@103: # cache miss, render terom@103: data = render_raw(image, width, height, x, y, zl) terom@103: terom@103: if cache : terom@103: # store terom@103: cache.add(key, data) terom@103: terom@103: # ok terom@103: return data terom@103: terom@92: ### Render PNG Data terom@103: def img_png_tile (image, x, y, zoom, cache) : terom@92: """ terom@92: Render given tile, returning PNG data terom@92: """ terom@92: terom@103: # do we want to cache this? terom@103: if check_cache_threshold(TILE_WIDTH, TILE_HEIGHT, zoom) : terom@103: # go via the cache terom@103: return render_cache(cache, image, TILE_WIDTH, TILE_HEIGHT, x, y, zoom) terom@103: terom@103: else : terom@103: # just go raw terom@103: return render_raw(image, TILE_WIDTH, TILE_HEIGHT, x, y, zoom) terom@103: terom@103: def img_png_region (image, cx, cy, zoom, width, height, cache) : terom@92: """ terom@92: Render arbitrary tile, returning PNG data terom@92: """ terom@92: terom@128: x = cx - width / 2 terom@128: y = cy - height / 2 terom@92: terom@92: # safely limit terom@92: if width * height > MAX_PIXELS : terom@92: raise ValueError("Image size: %d * %d > %d" % (width, height, MAX_PIXELS)) terom@103: terom@103: # these images are always cached terom@103: return render_cache(cache, image, width, height, x, y, zoom) terom@92: