class RendererLoopBreak(BaseException):
    pass

class Renderer:
    """
    Class responsible for updating tiles, their states, animations, etc.

    In the future, also takes in a WaterLayer and updates it with the game map.
    """
    def __init__(self):
        self.tiles = []
        # location of the top left corner of the viewpoint
        self.pos = [0, 0]
        self.viewport = [80, 24]

    def addTile(self, tile):
        self.tiles.append(tile)

    def massUpdate(self):
        for i in self.tiles:
            if i.ttype == "standard":
                i.update(self.tiles)

    def selectForRendering(self):
        """
        Returns what tiles are in the viewport.
        """

        tilesInScene = []

        for i in self.tiles:
            dims = i.dims
            pos = i.getCoords()

            try:
                for j in range(dims[0]):
                    for k in range(dims[1]):
                        if self.inViewport([pos[0] + j, pos[1] + k]):
                            tilesInScene.append(i)
                            raise RendererLoopBreak
            except RendererLoopBreak:
                pass

        self.cachedTiles = tilesInScene

        return tilesInScene