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"""
Tasks
-----
DONE *. Change all rect classes to use a sequence instead of 4 separate args
*. Implement a clear_rect that takes a rect argument and a color.
*. Rename the clear() method to ?erase()? so that clear can stick with
the clear_rect semantics.
*. Implement arc.
*. Implement a clear_rects that takes a rect list and a color.
*. Implement clipping to multiple rectangles.
Needed Tests
------------
Coordinate system offset.
DONE 1. Test that aliased line at zero puts full energy in last
row of buffer.
DONE 2. Test that antialiased line at zero puts half energy in
last row of buffer.
Aliased
DONE 1. For simple line, test all paths through rendering pipeline.
Antialiased
DONE 1. For simple line, test all paths through rendering pipeline.
Caps
DONE 1. Each version same for all paths through aliased code.
2. Each version same for all paths through antialiased code.
Joins (in join_stroke_path_test_case.py)
DONE 1. Each version same for all paths through aliased code.
DONE 2. Each version same for all paths through antialiased code.
Dashed Lines
*. Should be tested for all versions of aliasing and all versions
of join, cap.
Curved Lines
DONE *. curve_to
Note: There are numerous comments in code that refer to implementation
details (outline, outline_aa, scanline_aa, etc.) from the C++
code. These are largely to help keep track of what paths have
been tested.
"""
import unittest
from numpy import array, alltrue, ravel
from kiva.agg import GraphicsContextArray
import kiva
from test_utils import Utils
class StrokePathTestCase(unittest.TestCase, Utils):
def test_alias_width_one(self):
""" The fastest path through the stroke path code is for aliased
path with width=1. It is reasonably safe here not to worry
with testing all the CAP/JOIN combinations because they are
all rendered the same for this case.
It is handled by the agg::rasterizer_outline and the
agg::renderer_primitives classes in C++.
Energy for an aliased horizontal line of width=1 falls
within a single line of pixels. With y=0 for this line, the
engine should paint a single row of zeros along the
bottom edge of the bmp array.
"""
gc = GraphicsContextArray((3, 2), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(0, 0)
gc.line_to(3, 0)
# These settings allow the fastest path.
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(False)
gc.set_line_width(1)
gc.stroke_path()
# test a single color channel.
desired = array(((255,255,255),
( 0, 0, 0)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(actual, desired)
def test_alias_width_two_outline_aa(self):
""" When width>1, alias text is drawn using a couple of different
paths through the underlying C++ code. This test the faster of the
two which uses the agg::rasterizer_outline_aa C++ code. It is only
used when 2<=width<=10, and cap is ROUND or BUTT, and join is MITER
The C++ classes used in the underlying C++ code for this is
agg::rasterizer_outline_aa and agg::renderer_outline_aa
"""
gc = GraphicsContextArray((3, 2), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(0, 0)
gc.line_to(3, 0)
# Settings allow the 2nd fastest path.
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(False)
gc.set_line_width(2)
gc.set_line_cap(kiva.CAP_ROUND)
gc.set_line_join(kiva.JOIN_MITER)
gc.stroke_path()
# test a single color channel.
desired = array(((255, 255, 255),
( 0, 0, 0)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(actual, desired)
def test_alias_width_two_scanline_aa(self):
""" When width > 1, alias text is drawn using a couple of different
paths through the underlying C++ code. This test the slower of the
two which uses the agg::rasterizer_scanline_aa C++ code. We've set
the line join to bevel to trigger this path.
"""
gc = GraphicsContextArray((3, 2), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(0, 0)
gc.line_to(3, 0)
# Settings allow the 2nd fastest path.
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(False)
gc.set_line_width(2)
gc.set_line_cap(kiva.CAP_ROUND)
gc.set_line_join(kiva.JOIN_BEVEL)
gc.stroke_path()
# test a single color channel.
desired = array(((255, 255, 255),
( 0, 0, 0)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(actual, desired)
#########################################################################
# Cap Tests
#########################################################################
def cap_equality_helper(self, antialias, width, line_cap, line_join,
size=(6,6)):
gc = GraphicsContextArray(size, pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(2, 3)
gc.line_to(4, 3)
# Settings allow the faster outline path through C++ code
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(antialias)
gc.set_line_width(width)
gc.set_line_cap(line_cap)
gc.set_line_join(line_join)
gc.stroke_path()
return gc
def test_alias_cap_round(self):
""" Round caps should extend beyond the end of the line. We
don't really test the shape here. To do this, a test of
a wider line would be needed.
fix me: This is rendering antialiased end points currently.
"""
gc = GraphicsContextArray((6,6), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(2, 3)
gc.line_to(4, 3)
# Set up line
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(False)
gc.set_line_width(2)
gc.set_line_cap(kiva.CAP_ROUND)
gc.set_line_join(kiva.JOIN_MITER)
gc.stroke_path()
desired = array(((255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255),
(255, 0, 0, 0, 0, 255),
(255, 0, 0, 0, 0, 255),
(255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(desired, actual)
def test_alias_cap_round_equality(self):
""" There are two paths that can generate aliased round capped lines.
This tests that they generate equivalent results
fix me: This test fails because the two rendering paths
render the end caps differently.
"""
antialias = False
width = 2
cap = kiva.CAP_ROUND
# join=miter allows the faster outline path through C++ code.
gc1 = self.cap_equality_helper(antialias, width, cap, kiva.JOIN_MITER)
# join=bevel forces the scanline path through C++ code.
gc2 = self.cap_equality_helper(antialias, width, cap, kiva.JOIN_BEVEL)
# Instead of testing against a known desired value, we are simply
# testing for equality...
self.assertRavelEqual(gc1.bmp_array[:,:,0], gc2.bmp_array[:,:,0])
def test_alias_cap_square(self):
""" Round caps should extend beyond the end of the line. by
half the width of the line.
fix me: This is rendering antialiased end points currently.
"""
gc = GraphicsContextArray((6,6), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(2, 3)
gc.line_to(4, 3)
# Set up line
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(False)
gc.set_line_width(2)
gc.set_line_cap(kiva.CAP_SQUARE)
gc.set_line_join(kiva.JOIN_MITER)
gc.stroke_path()
desired = array(((255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255),
(255, 255, 0, 0, 255, 255),
(255, 255, 0, 0, 255, 255),
(255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(desired, actual)
def test_alias_cap_square(self):
""" Square caps should extend beyond the end of the line. by
half the width of the line.
"""
gc = GraphicsContextArray((6,6), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(2, 3)
gc.line_to(4, 3)
# Set up line
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(False)
gc.set_line_width(2)
gc.set_line_cap(kiva.CAP_SQUARE)
gc.set_line_join(kiva.JOIN_MITER)
gc.stroke_path()
desired = array(((255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255),
(255, 0, 0, 0, 0, 255),
(255, 0, 0, 0, 0, 255),
(255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(desired, actual)
def test_alias_cap_butt_equality(self):
""" There are two paths that can generate aliased butt capped lines.
This tests that they generate equivalent results
"""
antialias = False
width = 2
cap = kiva.CAP_BUTT
# join=miter allows the faster outline path through C++ code.
gc1 = self.cap_equality_helper(antialias, width, cap, kiva.JOIN_MITER)
# join=bevel forces the scanline path through C++ code.
gc2 = self.cap_equality_helper(antialias, width, cap, kiva.JOIN_BEVEL)
# Instead of testing against a known desired value, we are simply
# testing for equality...
self.assertRavelEqual(gc1.bmp_array, gc2.bmp_array)
def test_alias_cap_square(self):
""" Square caps should extend beyond the end of the line. by
half the width of the line.
"""
gc = GraphicsContextArray((6,6), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(2, 3)
gc.line_to(4, 3)
# Set up line
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(False)
gc.set_line_width(2)
gc.set_line_cap(kiva.CAP_SQUARE)
gc.set_line_join(kiva.JOIN_MITER)
gc.stroke_path()
desired = array(((255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255),
(255, 0, 0, 0, 0, 255),
(255, 0, 0, 0, 0, 255),
(255, 255, 255, 255, 255, 255),
(255, 255, 255, 255, 255, 255)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(desired, actual)
def test_alias_cap_square_equality(self):
""" There are two paths that can generate aliased square capped lines.
This tests that they generate equivalent results.
"""
antialias = False
width = 2
cap = kiva.CAP_SQUARE
# join=miter allows the faster outline path through C++ code.
gc1 = self.cap_equality_helper(antialias, width, cap, kiva.JOIN_MITER)
# join=bevel forces the scanline path through C++ code.
gc2 = self.cap_equality_helper(antialias, width, cap, kiva.JOIN_BEVEL)
# Instead of testing against a known desired value, we are simply
# testing for equality...
self.assertRavelEqual(gc1.bmp_array, gc2.bmp_array)
def test_antialias_width_one(self):
""" An anti-aliased horizontal line of width=1 has its energy
centered between the bottom row of pixels and the next lower
row of pixels (which is off the page). It dumps half
its energy in each, so we end up with a single line of
127,127,127 pixel values in the last row of pixels.
This particular set of flags is handled by the (fast)
agg::rasterizer_outline_aa path through the C++ code.
"""
gc = GraphicsContextArray((3, 2), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(0, 0)
gc.line_to(3, 0)
# Set up stroke
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(True)
gc.set_line_width(1)
gc.set_line_cap(kiva.CAP_BUTT)
gc.set_line_join(kiva.JOIN_MITER)
gc.stroke_path()
# test a single color channel.
desired = array(((255, 255, 255),
(127, 127, 127)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(desired, actual)
def test_antialias_width_slower_path(self):
""" An anti-aliased horizontal line of width=1 has its energy
centered between the bottom row of pixels and the next lower
row of pixels (which is off the page). It dumps half
its energy in each, so we end up with a single line of
127,127,127 pixel values in the last row of pixels.
This particular set of flags is handled by the
agg::rasterizer_scanline_aa path through the C++ code.
"""
gc = GraphicsContextArray((3, 2), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
gc.move_to(0, 0)
gc.line_to(3, 0)
# Set up stroke
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(True)
gc.set_line_width(1)
gc.set_line_cap(kiva.CAP_BUTT)
gc.set_line_join(kiva.JOIN_BEVEL)
gc.stroke_path()
# test a single color channel.
desired = array(((255, 255, 255),
(127, 127, 127)))
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(desired, actual)
def test_curve_to(self):
""" curve_to
conv_curve happens early in the agg rendering pipeline,
so it isn't neccessary to test every combination of
antialias, line_cap, line_join, etc. If it works for
one, we should be in good shape for the others (until
the implementation is changed of course...)
"""
gc = GraphicsContextArray((10, 10), pix_format="rgb24")
# clear background to white values (255, 255, 255)
gc.clear((1.0, 1.0, 1.0))
# single horizontal line across bottom of buffer
x0, y0 = 1.0, 5.0
x1, y1 = 4.0, 9.0
x2, y2 = 6.0, 1.0
x3, y3 = 9.0, 5.0
gc.move_to(x0, y0)
gc.curve_to(x1, y1, x2, y2, x3, y3);
# Set up stroke
gc. set_stroke_color((0.0, 0.0, 0.0)) # black
gc.set_antialias(True)
gc.set_line_width(1)
gc.set_line_cap(kiva.CAP_BUTT)
gc.set_line_join(kiva.JOIN_MITER)
gc.stroke_path()
gc. set_stroke_color((0.0, 1.0, 1.0))
gc.move_to(x0, y0)
gc.line_to(x1, y1)
gc.move_to(x2, y2)
gc.line_to(x3, y3)
gc.stroke_path()
# test a single color channel.
# note: This is a "screen capture" from running this
# test. It looks right, but hasn't been check closely.
desired = array([[255, 255, 255, 230, 255, 255, 255, 255, 255, 255],
[255, 255, 231, 25, 212, 255, 255, 255, 255, 255],
[255, 252, 65, 128, 255, 255, 255, 255, 255, 255],
[255, 103, 26, 143, 229, 255, 255, 255, 255, 255],
[179, 2, 115, 96, 23, 189, 255, 255, 204, 255],
[255, 205, 255, 255, 189, 23, 97, 116, 2, 179],
[255, 255, 255, 255, 255, 229, 142, 25, 103, 255],
[255, 255, 255, 255, 255, 255, 127, 66, 252, 255],
[255, 255, 255, 255, 255, 212, 26, 231, 255, 255],
[255, 255, 255, 255, 255, 255, 231, 255, 255, 255]])
actual = gc.bmp_array[:,:,0]
self.assertRavelEqual(desired, actual)
if __name__ == "__main__":
unittest.main()
|
