def __init__(self):
"""
AbstractPlot is a class to draw coordinate system
"""
self._coordinates_thickness = 2
self._coordinates_color = Color('#394659')
self._grid_padding = 20
self._grid_color = Color('#A5C9FF')
self._resolution = Resolution(800,600)
self._image = Image.new('RGBA', tuple(self._resolution), tuple(Color('#fff')))
class AbstractPlot(object):
def __init__(self):
"""
AbstractPlot is a class to draw coordinate system
"""
self._coordinates_thickness = 2
self._coordinates_color = Color('#394659')
self._grid_padding = 20
self._grid_color = Color('#A5C9FF')
self._resolution = Resolution(800,600)
self._image = Image.new('RGBA', tuple(self._resolution), tuple(Color('#fff')))
def get_resolution(self):
"""
return resolution of plot (Resolution object)
"""
return self._resolution
def _get_center(self):
"""
This is interface who calculate center of plot, by default is center of available space
"""
return self._resolution.get_center()
def _draw_coordinates(self, draw):
"""
this method draw coordinates line
"""
center = self._get_center()
draw.line([(center.x,0),(center.x, self._resolution.height)],
fill = tuple(self._coordinates_color), width = self._coordinates_thickness)
draw.line([(0,center.y),(self._resolution.width, center.y)],
fill = tuple(self._coordinates_color), width = self._coordinates_thickness)
# draw arrows
# TODO : antialiasing for that
p1 = Point(self._resolution.width - 10, center.y - 6)
p2 = Point(self._resolution.width, center.y)
p3 = Point(self._resolution.width - 10, center.y + 6)
draw.polygon((tuple(p1),tuple(p2), tuple(p3)), fill = tuple(self._coordinates_color))
p1 = Point(center.x - 6, 10)
p2 = Point(center.x, 0)
p3 = Point(center.x + 6, 10)
draw.polygon((tuple(p1),tuple(p2), tuple(p3)), fill = tuple(self._coordinates_color))
def _draw_grid(self, draw):
"""
this method draw grid
"""
width, height = tuple(self._resolution)
vertical_lines = (((x, 0),(x, height)) \
for x in xrange(self._grid_padding, width, self._grid_padding))
horizontal_lines = (((0, y), (width, y)) \
for y in xrange(self._grid_padding, height, self._grid_padding))
draw_line = lambda points: draw.line(points, fill = tuple(self._grid_color), width = 1)
map(draw_line, vertical_lines)
map(draw_line, horizontal_lines)
def _draw(self):
"""
this method draw all elements of chart
"""
draw = ImageDraw.ImageDraw(self._image)
self._draw_grid(draw)
self._draw_coordinates(draw)
del draw
def save_as_png(self, file_path):
"""
save created image to file (now is draw all part of chart with actual settings)
"""
self._draw()
self._image.save(file_path, "PNG")