def draw(ctx, width, height, frame_no, frame_count):
ctx.set_source_rgba(*Color(1).get_rgba())
ctx.paint()
for i in range(200):
ctx.set_source_rgba(*Color.of_hsl(i / 200, 1, 0.5).get_rgba())
ctx.rectangle(i + 50, 50, 1, 50)
ctx.fill()
for i in range(200):
ctx.set_source_rgba(*Color.of_hsl(0.25, i / 200, 0.5).get_rgba())
ctx.rectangle(i + 50, 150, 1, 50)
ctx.fill()
for i in range(200):
ctx.set_source_rgba(*Color.of_hsl(0.25, 1, i / 200).get_rgba())
ctx.rectangle(i + 50, 250, 1, 50)
ctx.fill()
def draw(ctx, width, height, frame_no, frame_count):
ctx.set_source_rgba(*Color(1).get_rgba())
ctx.paint()
ctx.set_source_rgba(*Color.of_hsl(0, 0.5, 0.5).get_rgba())
ctx.rectangle(50, 50, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0.33, 0.5, 0.5).get_rgba())
ctx.rectangle(200, 50, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0.66, 0.5, 0.5).get_rgba())
ctx.rectangle(350, 50, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0, 0.25, 0.5).get_rgba())
ctx.rectangle(50, 200, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0, 0.5, 0.25).get_rgba())
ctx.rectangle(200, 200, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0, 0.5, 0.5).get_rgba())
ctx.rectangle(330, 180, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsla(0.5, 0.5, 0.5, 0.5).get_rgba())
ctx.rectangle(370, 220, 100, 100)
ctx.fill()
def draw(ctx, width, height, frame_no, frame_count):
ctx.set_source_rgba(*Color(0))
ctx.paint()
# Vary hue, with s = 1, l = 0.5.
# The hue is the position on the colour circle:
# - hue 0 is pure red
# - as hue increases the colour moves through yellow towards green
# - hue 0.33 is pure green
# - as hue increases the colour moves through cyan towards blue
# - hue 0.66 is pure blue
# - as hue increases the colour moves through magenta towards red
# - as the hue approaches 1, the colour goes back to pure red.
# This is a circular parameter, th eci#ycle starts again at 1
for i in range(200):
ctx.set_source_rgba(*Color.of_hsl(i / 200, 1, 0.5))
ctx.rectangle(2 * i + 100, 100, 2, 100)
ctx.fill()
# Vary saturation, with h = 0.33 (green), l = 0.5.
# With saturation 1, the colour is pure (fully saturated).
# Reducing the saturation makes the colour more "grey".
# When the saturation is 0, the colour is totally grey. All hues look identical ar zero saturation,
# they all become the same grey (the shade og grey depends on the lightness value)
for i in range(200):
ctx.set_source_rgba(*Color.of_hsl(0.33, i / 200, 0.5))
ctx.rectangle(2 * i + 100, 300, 2, 100)
ctx.fill()
# Vary lightness, with h = 0.33 (green), s = 1.
# Changing the lightness creates lighter or darker versions of the same colour,
# rather like looking at the same object in a brighter or darker room.
# When lightness is 0, all colours are black. When lightness is 1, all colours are white.
for i in range(200):
ctx.set_source_rgba(*Color.of_hsl(0.33, 1, i / 200))
ctx.rectangle(2 * i + 100, 500, 2, 100)
ctx.fill()
def draw(ctx, width, height, frame_no, frame_count):
ctx.set_source_rgba(*Color(1))
ctx.paint()
# We use Color.of_hsl() to create an HSL colour.
# A hue of 0 gives pure red. We then set the saturation ot 0.5, which greys the colour
# out a little, and lightness to 0.5 which creates a slightly dark red.
ctx.set_source_rgba(*Color.of_hsl(0, 0.5, 0.5))
ctx.rectangle(50, 50, 100, 100)
ctx.fill()
# Same as before, but a hue of 0.33 gives the equivalent green colour
ctx.set_source_rgba(*Color.of_hsl(0.33, 0.5, 0.5))
ctx.rectangle(200, 50, 100, 100)
ctx.fill()
# Same as before, but a hue of 0.66 gives the equivalent blue colour
ctx.set_source_rgba(*Color.of_hsl(0.66, 0.5, 0.5))
ctx.rectangle(350, 50, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0, 0.25, 0.5))
ctx.rectangle(50, 200, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0, 0.5, 0.25))
ctx.rectangle(200, 200, 100, 100)
ctx.fill()
ctx.set_source_rgba(*Color.of_hsl(0, 0.5, 0.5))
ctx.rectangle(330, 180, 100, 100)
ctx.fill()
# Here we create a rectangle with a colour Color.of_hsla(0.5, 0.5, 0.5, 0.3).
# That is blue-green with a 0.3 alpha value (30% opacity, ie 70% transparent).
# This overlaps the previous rectangle, and you can see the background through it.
ctx.set_source_rgba(*Color.of_hsla(0.5, 0.5, 0.5, 0.3))
ctx.rectangle(370, 220, 100, 100)
ctx.fill()
def draw_hsl(ctx, pixel_width, pixel_height, frame_no, frame_count):
setup(ctx, pixel_width, pixel_height, background=Color('cornflowerblue'))
pos = [10, 10]
w = 70
h = 100
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.1, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.2, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.3, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.4, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.5, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.6, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.7, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.8, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.9, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(1.0, 0.5, 0.5))
pos[0] += w
pos = [10, 120]
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.0, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.1, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.2, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.3, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.4, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.6, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.7, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.8, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 0.9, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.0, 1.0, 0.5))
pos[0] += w
pos = [10, 230]
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.0))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.1))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.2))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.3))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.4))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.5))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.6))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.7))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.8))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 0.9))
pos[0] += w
Rectangle(ctx).of_corner_size(pos, w, h).fill(Color.of_hsl(0.66, 0.5, 1.0))
pos[0] += w
