Source code for cartopy.mpl.slippy_image_artist

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Define the SlippyImageArtist class, which interfaces with
:class:`` instances at draw time, for interactive
dragging and zooming of raster data.


from __future__ import (absolute_import, division, print_function)

from matplotlib.image import AxesImage
import matplotlib.artist

[docs]class SlippyImageArtist(AxesImage): """ A subclass of :class:`~matplotlib.image.AxesImage` which provides an interface for getting a raster from the given object with interactive slippy map type functionality. Kwargs are passed to the AxesImage constructor. """ def __init__(self, ax, raster_source, **kwargs): self.raster_source = raster_source super(SlippyImageArtist, self).__init__(ax, **kwargs) self.set_clip_path(ax.outline_patch) @matplotlib.artist.allow_rasterization def draw(self, renderer, *args, **kwargs): if not self.get_visible(): return ax = self.axes window_extent = ax.get_window_extent() [x1, y1], [x2, y2] = ax.viewLim.get_points() located_images = self.raster_source.fetch_raster( ax.projection, extent=[x1, x2, y1, y2], target_resolution=(window_extent.width, window_extent.height)) for img, extent in located_images: self.set_array(img) with ax.hold_limits(): self.set_extent(extent)
super(SlippyImageArtist, self).draw(renderer, *args, **kwargs)