def test_scaling_outputs(self):
surface_types = [('pdf', 1), ('svg', 1), ('png', 0.5), ('png', 1),
('png', 2)]
units = ['pt', 'in', 'cm', 'mm', 'px']
for (surface_type, pixel_scale_factor) in surface_types:
for unit in units:
canvas_builder = CanvasBuilder()
# We want to test all units, but some sizes are just too big
# and will take up lots of disk space. So we make an exception
# for inches and centimeters.
expected_size_in_unit: int
expected_size: Optional[CanvasUnit]
if unit in ['in', 'cm']:
expected_size_in_unit = 4
expected_size = Cu.from_unit(4, unit)
# Setting to a smaller size to avoid disk space issues
canvas_builder.set_size(expected_size, expected_size)
else:
expected_size_in_unit = 100
expected_size = CanvasUnit.from_unit(100, unit)
canvas_builder.set_size(expected_size, expected_size)
path = Path(__file__).parent \
.joinpath(
'output/canvas_builder_%s_%d%s_x%s.%s' %
(
surface_type,
expected_size_in_unit,
unit,
pixel_scale_factor,
surface_type
)
)
path.unlink(missing_ok=True)
canvas_builder.set_path(path)
canvas_builder.set_pixel_scale_factor(pixel_scale_factor)
canvas = canvas_builder.build()
self.draw_rectangle_top_left(canvas, unit)
canvas.close()
assert path.exists()
actual = self.get_file_dimensions_and_scale(path)
if surface_type == 'pdf':
self.assert_match(expected_size_in_unit, unit,
surface_type, 1, actual,
expected_size.pt)
elif surface_type == 'svg':
self.assert_match(expected_size_in_unit, unit,
surface_type, 1, actual,
expected_size.pt)
elif surface_type == 'png':
self.assert_match(expected_size_in_unit, unit,
surface_type, pixel_scale_factor, actual,
expected_size.px)
def draw_rectangle_top_left(canvas: Canvas, unit: str):
if unit in ['in', 'cm']:
# Setting to a smaller size to avoid disk space issues
midpoint = CanvasUnit.from_unit(2, unit).pt
else:
midpoint = CanvasUnit.from_unit(50, unit).pt
top_left = (0, 0)
top_right = (midpoint, 0)
bottom_left = (0, midpoint)
bottom_right = (midpoint, midpoint)
shape = Polygon(
[top_left, top_right, bottom_right, bottom_left, top_left])
canvas.context.set_source_rgb(0, 0, 0)
CairoHelper.draw_polygon(canvas.context, shape)
canvas.context.fill()
point_unit_shape = Polygon([(0, 0), (0, 1), (1, 1), (1, 0), (0, 0)])
canvas.context.set_source_rgb(1, 0, 0)
CairoHelper.draw_polygon(canvas.context, point_unit_shape)
canvas.context.fill()
def draw_rectangle(self, canvas: Canvas, offset: int, unit: str):
height = CanvasUnit.from_pt(10).pt
width = CanvasUnit.from_unit(1, unit).pt
offset_height = height * offset
top_left = (0, offset_height)
top_right = (width, offset_height)
bottom_left = (0, offset_height + height)
bottom_right = (width, offset_height + height)
shape = Polygon([
top_left,
top_right,
bottom_right,
bottom_left,
top_left
])
canvas.context.set_source_rgba(*self.color)
CairoHelper.draw_polygon(canvas.context, shape)
canvas.context.set_source_rgba(0.5, 0.5, 0.5, 1)
canvas.context.fill()
def test_unknown_unit(self):
with self.assertRaises(Exception):
CanvasUnit.from_unit(1, 'unknown')
