Drawing

New in version 0.3.0.

The wand.drawing module provides some basic drawing functions. wand.drawing.Drawing object buffers instructions for drawing shapes into images, and then it can draw these shapes into zero or more images.

It’s also callable and takes an Image object:

from wand.drawing import Drawing
from wand.image import Image

with Drawing() as draw:
    # does something with ``draw`` object,
    # and then...
    with Image(filename='wandtests/assets/beach.jpg') as image:
        draw(image)

Arc

New in version 0.4.0.

Arcs can be drawn by using arc() method. You’ll need to define three pairs of (x, y) coordinates. First & second pair of coordinates will be the minimum bounding rectangle, and the last pair define the starting & ending degree.

An example:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.stroke_color = Color('black')
    draw.stroke_width = 2
    draw.fill_color = Color('white')
    draw.arc(( 25, 25),  # Stating point
             ( 75, 75),  # Ending point
             (135,-45))  # From bottom left around to top right
    with Image(width=100,
               height=100,
               background=Color('lightblue')) as img:
        draw.draw(img)
        img.save(filename='draw-arc.gif')
draw-arc.gif

Bezier

New in version 0.4.0.

You can draw bezier curves using bezier() method. This method requires at least four points to determine a bezier curve. Given as a list of (x, y) coordinates. The first & last pair of coordinates are treated as start & end, and the second & third pair of coordinates act as controls.

For example:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.stroke_color = Color('black')
    draw.stroke_width = 2
    draw.fill_color = Color('white')
    points = [(10,50),  # Start point
              (50,10),  # First control
              (50,90),  # Second control
              (90,50)]  # End point
    draw.bezier(points)
    with Image(width=100,
               height=100,
               background=Color('lightblue')) as image:
        draw(image)
draw-bezier.gif

Control width & color of curve with the drawing properties:

Circle

New in version 0.4.0.

You can draw circles using circle() method. Circles are drawn by defining two pairs of (x, y) coordinates. First coordinate for the center “origin” point, and a second pair for the outer perimeter. For example, the following code draws a circle in the middle of the image:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.stroke_color = Color('black')
    draw.stroke_width = 2
    draw.fill_color = Color('white')
    draw.circle((50, 50), # Center point
                (25, 25)) # Perimeter point
    with Image(width=100, height=100, background=Color('lightblue')) as image:
        draw(image)
draw-circle.gif

Color & Matte

New in version 0.4.0.

You can draw with colors directly on the coordinate system of an image. Define which color to set by setting fill_color. The behavior of color() is controlled by setting one of PAINT_METHOD_TYPES paint methods.

  • 'point' alters a single pixel.
  • 'replace' swaps on color for another. Threshold is influenced by fuzz.
  • 'floodfill' fills area of a color influenced by fuzz.
  • 'filltoborder' fills area of a color until border defined by border_color.
  • 'reset' replaces the whole image to a single color.

Example fill all to green boarder:

from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.border_color = Color('green')
    draw.fill_color = Color('blue')
    draw.color(15, 25, 'filltoborder')

The matte() method is identical to the color() method above, but alters the alpha channel of the color area selected. Colors can be manipulated, but not replaced.

with Drawing() as draw:
    draw.fill_color = None  # or Color('none')
    draw.matte(15, 25, 'floodfill')

Composite

New in version 0.4.0.

Similar to composite_channel(), this composite() method will render a given image on top of the drawing subject image following the COMPOSITE_OPERATORS options. An compositing image must be given with a destination top, left, width, and height values.

from wand.image import Image, COMPOSITE_OPERATORS
from wand.drawing import Drawing
from wand.display import display

wizard = Image(filename='wizard:')
rose = Image(filename='rose:')

for o in COMPOSITE_OPERATORS:
  w = wizard.clone()
  r = rose.clone()
  with Drawing() as draw:
    draw.composite(operator=o, left=175, top=250,
                   width=r.width, height=r.height, image=r)
    draw(w)
    display(w)

Ellipse

New in version 0.4.0.

Ellipse can be drawn by using the ellipse() method. Like drawing circles, the ellipse requires a origin point, however, a pair of (x, y) radius are used in relationship to the origin coordinate. By default a complete “closed” ellipse is drawn. To draw a partial ellipse, provide a pair of starting & ending degrees as the third parameter.

An example of a full ellipse:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.stroke_color = Color('black')
    draw.stroke_width = 2
    draw.fill_color = Color('white')
    draw.ellipse((50, 50), # Origin (center) point
                 (40, 20)) # 80px wide, and 40px tall
    with Image(width=100, height=100, background=Color('lightblue')) as image:
        draw(image)
draw-ellipse-full.gif

Same example as above, but with a half-partial ellipse defined by the third parameter:

draw.ellipse((50, 50), # Origin (center) point
             (40, 20), # 80px wide, and 40px tall
             (90,-90)) # Draw half of ellipse from bottom to top
draw-ellipse-part.gif

Lines

You can draw lines using line() method. It simply takes two (x, y) coordinates for start and end of a line. For example, the following code draws a diagonal line into the image:

draw.line((0, 0), image.size)
draw(image)

Or you can turn this diagonal line upside down:

draw.line((0, image.height), (image.width, 0))
draw(image)

The line color is determined by fill_color property, and you can change this of course. The following code draws a red diagonal line into the image:

from wand.color import Color

with Color('red') as color:
    draw.fill_color = color
    draw.line((0, 0), image.size)
    draw(image)

Paths

New in version 0.4.0.

Paths can be drawn by using any collection of path functions between path_start() and path_finish() methods. The available path functions are:

Each path method expects a destination point, and will draw from the current point to the new point. The destination point will become the new current point for the next applied path method. Destination points are given in the form of (x, y) coordinates to the to parameter, and can by relative or absolute to the current point by setting the relative flag. The path_curve() and path_curve_to_quadratic_bezier() expect additional control points, and can complement previous drawn curves by setting a smooth flag. When the smooth flag is set to True the first control point is assumed to be the reflection of the last defined control point.

For example:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.stroke_width = 2
    draw.stroke_color = Color('black')
    draw.fill_color = Color('white')
    draw.path_start()
    # Start middle-left
    draw.path_move(to=(10, 50))
    # Curve accross top-left to center
    draw.path_curve(to=(40, 0),
                    controls=[(10, -40), (30,-40)],
                    relative=True)
    # Continue curve accross bottom-right
    draw.path_curve(to=(40, 0),
                    controls=(30, 40),
                    smooth=True,
                    relative=True)
    # Line to top-right
    draw.path_vertical_line(10)
    # Diagonal line to bottom-left
    draw.path_line(to=(10, 90))
    # Close first & last points
    draw.path_close()
    draw.path_finish()
    with Image(width=100, height=100, background=Color('lightblue')) as image:
        draw(image)
draw-path.gif

Point

New in version 0.4.0.

You can draw points by using point() method. It simply takes two x, y arguments for the point coordinate.

The following example will draw points following a math function across a given image:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color
import math

with Drawing() as draw:
    for x in xrange(0, 100):
        y = math.tan(x) * 4
        draw.point(x, y + 50)
    with Image(width=100, height=100, background=Color('lightblue')) as image:
        draw(image)
draw-point-math.gif

Color of the point can be defined by setting the following property

Polygon

New in version 0.4.0.

Complex shapes can be created with the polygon() method. You can draw a polygon by given this method a list of points. Stroke line will automatically close between first & last point.

For example, the following code will draw a triangle into the image:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.stroke_width = 2
    draw.stroke_color = Color('black')
    draw.fill_color = Color('white')
    points = [(25, 25), (75, 50), (25, 75)]
    draw.polygon(points)
    with Image(width=100, height=100, background=Color('lightblue')) as image:
        draw(image)
draw-polygon.gif

Control the fill & stroke with the following properties:

Polyline

New in version 0.4.0.

Identical to polygon(), except polyline() will not close the stroke line between the first & last point.

For example, the following code will draw a two line path on the image:

from wand.image import Image
from wand.drawing import Drawing
from wand.color import Color

with Drawing() as draw:
    draw.stroke_width = 2
    draw.stroke_color = Color('black')
    draw.fill_color = Color('white')
    points = [(25, 25), (75, 50), (25, 75)]
    draw.polyline(points)
    with Image(width=100, height=100, background=Color('lightblue')) as image:
        draw(image)
draw-polyline.gif

Control the fill & stroke with the following properties:

Push & Pop

New in version 0.4.0.

When working with complex vector graphics, you can use ImageMagick’s internal graphic-context stack to manage different styles & operations. The methods push(), push_clip_path(), push_defs(), and push_pattern() are used to mark the beginning of a sub-routine. The clip path & pattern methods take a name based identifier argument, and can be referenced at a latter point with clip_path, or set_fill_pattern_url() / set_stroke_pattern_url() respectively. With stack management, pop() is used to mark the end of a sub-routine, and return the graphical context to its pervious state before push() was invoked. Methods pop_clip_path(), pop_defs(), and pop_pattern() exist to match there pop counterparts.

from wand.color import Color
from wand.image import Image
from wand.drawing import Drawing
from wand.compat import nested
from math import cos, pi, sin

with nested(Color('lightblue'),
            Color('transparent'),
            Drawing()) as (bg, fg, draw):
    draw.stroke_width = 3
    draw.fill_color = fg
    for degree in range(0, 360, 15):
        draw.push()  # Grow stack
        draw.stroke_color = Color('hsl({0}%, 100%, 50%)'.format(degree * 100 / 360))
        t = degree / 180.0 * pi
        x = 35 * cos(t) + 50
        y = 35 * sin(t) + 50
        draw.line((50, 50), (x, y))
        draw.pop()  # Restore stack
    with Image(width=100, height=100, background=Color('lightblue')) as img:
        draw(img)
../_images/draw-push-pop.gif

Rectangles

New in version 0.3.6.

Changed in version 0.4.0.

If you want to draw rectangles use rectangle() method. It takes left/top coordinate, and right/bottom coordinate, or width and height. For example, the following code draws a square on the image:

draw.rectangle(left=10, top=10, right=40, bottom=40)
draw(image)

Or using width and height instead of right and bottom:

draw.rectangle(left=10, top=10, width=30, height=30)
draw(image)

Support for rounded corners was added in version 0.4.0. The radius argument sets corner rounding.

draw.rectangle(left=10, top=10, width=30, height=30, radius=5)
draw(image)

Both horizontal & vertical can be set independently with xradius & yradius respectively.

draw.rectangle(left=10, top=10, width=30, height=30, xradius=5, yradius=3)
draw(image)

Note that the stoke and the fill are determined by the following properties:

Texts

Drawing object can write texts as well using its text() method. It takes x and y coordinates to be drawn and a string to write:

draw.font = 'wandtests/assets/League_Gothic.otf'
draw.font_size = 40
draw.text(image.width / 2, image.height / 2, 'Hello, world!')
draw(image)

As the above code shows you can adjust several settings before writing texts:

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