Agile SVG Maker

Need to draw hundreds of frames for a GIF? Need to change the style of all pictures in a PPT? Need to draw similar images with different parameters? Try ASVG!

Under construction, not so agile yet…

Basically aimed at academic illustrations.

Simple Example

from ASVG import *

# A 500x300 canvas
a = Axis((500, 300)) 

# Draw a rectangle on a, at level 1, from (0,0) to (200,100)
# With (5,5) round corner, fill with red color.
rect(a, 1, 0, 0, 200, 100, 5, 5, fill='red')

# Draw a circle on a, at level 3
# Centered (50,50) with 50 radius, fill with blue color.
circle(a, 3, 50, 50, 50, fill='blue')

# Draw this picture to example.svg
draw(a, "example.svg")

Parameterized Sub-image

def labeledRect(
        level: int,
        width: float,
        height: float,
        s: Union[str, TextRepresent],
        font_size: float,
        textShift: Tuple[float, float] = (0, 0),
        font: str = "Arial",
        rx: float = 0,
        ry: float = 0,
        margin: float = 5,
        attrib: Attrib = Attrib(),
        rectAttrib: Attrib = Attrib(),
        textAttrib: Attrib = Attrib(),
        **kwargs):
    e = ComposedElement((width + 2 * margin, height + 2 * margin),
                        level, attrib + kwargs)
    rect(e, 0, margin, margin, width, height, rx, ry, attrib=rectAttrib)

    textX = width / 2 + textShift[0] + margin
    textY = height / 2 + textShift[1] + (font_size / 2) + margin
    text(e, 1, s, textX, textY, font_size, font, attrib=textAttrib)
    return e

a = Axis((300,200))
a.addElement(labeledRect(...))

Nested Canvas

Canvas and Axis

Create a canvas axis with Axis(size, viewport)
size=(width, height) is the physical size of the canvas in pixels.
viewport=(x, y) is the logical size of the axis, by default its the same of the physical size.

# A 1600x900 canvas, axis range [0,1600)x[0,900)
a = Axis((1600, 900))

# A 1600x900 canva, with normalized axis range[0,1),[0,1)
b = Axis((1600, 900), (1.0, 1.0))

ComposedElement

A composed element is a sub-image.

ComposedElement(size, level, attrib)
size=(width, height): the size of the axis of this element.
level: the higher the level is, the fronter the composed element is.
attrib: the common attributes of this element

Add a composed element into the big canvas:axis.addElement(element, shift)
shift=(x,y) is the displacement of the element in the outer axis.

A composed element can have other composed elements as sub-pictures:
element.addElement(subElement, shift)

Basic Elements

The basic element comes from SVG.
Basicly, every element needs a axis and a level argument.
axis can be a Axis or ComposedElement.
The bigger the level is, the fronter the element is.
level is only comparable when two elements are under the same axis.

# Rectangle
rect(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    x: float, # top left
    y: float,
    width: float,
    height: float,
    rx: float = 0.0, # round corner radius
    ry: float = 0.0,
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)
# Circle
circle(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    cx: float, # center
    cy: float,
    r: float, # radius
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)
# Ellipse
ellipse(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    cx: float, # center
    cy: float,
    rx: float, # radius
    ry: float,
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)
# Straight line
line(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    x1: float, # Start
    y1: float,
    x2: float, # End
    y2: float,
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)
# Polyline
polyline(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    points: List[Tuple[float, float]],
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)
# Polygon
polygon(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    points: List[Tuple[float, float]],
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)
# Path
path(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    d: PathD,
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)

PathD is a sequence of path descriptions, the actions is like SVG’s path element. View Path tutorial
We use ?To() for captial letters and ?For() for lower-case letters. close() and open() is for closing or opening the path.
Example:

d = PathD()
d.moveTo(100,100)
d.hlineFor(90)
d.close()
# Equivilent: d = PathD(["M 80 80", "h 90",  "Z"])

path(a, 0, d)

Text

text(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    s: Union[str, TextRepresent],
    x: float,
    y: float,
    fontSize: int,
    font: str = "Arial",
    anchor: str = "middle",
    attrib: core.Attrib = core.Attrib(),
    **kwargs
)

anchor is where (x,y) is in the text. Can be either start, middle or end.

TextRepresent means formatted text.
Normal string with \n in it will be converted into multilines.
You can use TextSpan to add some attributes to a span of text.

Examples:

text(
    a, 10,
    "Hello\n???" + \
    TextSpan("!!!\n", fill='#00ffff', font_size=25) +\
    "???\nabcdef",
    30, 30, 20, anchor="start")

Arrow

# Straight arrow
arrow(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    x: float, # Position of the tip
    y: float,
    fromX: float, # Position of the other end
    fromY: float,
    tipSize: float = 10.0,
    tipAngle: float = 60.0,
    tipFilled: bool = True,
    **kwargs
)
# Polyline arrow
polyArrow(
    axis: Union[core.Axis, core.ComposedElement],
    level: int,
    points: List[Tuple[float, float]],
    tipSize: float = 10.0,
    tipAngle: float = 60.0,
    tipFilled: bool = True,
    **kwargs
)

Attributes

Attributes is for customizing the style of the elements.

myStyle = Attrib(
    fill = "#1bcd20",
    stroke = "black",
    stroke_width = "1pt"
)

alertStype = myStyle.copy()
alertStype.fill = "#ff0000"

rect(..., attrib=myStyle)
circle(..., attrib=alertStyle)

The name of the attribute are the same as in SVG elements, except use underline _ instead of dash -

Attributs of ComposedElement applies on <group> element.

For convinent, you can directly write some attributes in **kwargs.

rect(..., fill="red")

# Equivilient
rect(..., attrib=Attrib(fill="red))

GitHub

View Github