Getting Started#

PyScript#

proceso sketches run in your web browser, so all you need is a text editor to get started. Here is an example of how to create a proceso sketch with PyScript using Python, HTML, and CSS:

from proceso import Sketch


p5 = Sketch()
p5.describe("A white circle in the middle of a blue square.")

p5.background("cornflowerblue")
p5.circle(50, 50, 20)

<!DOCTYPE html>
<html lang="en-us">

<head>
    <title>My Sketch</title>
    <meta charset="utf-8" />

    <link rel="stylesheet" href="https://pyscript.net/releases/2023.05.1/pyscript.css" />
    <script defer src="https://pyscript.net/releases/2023.05.1/pyscript.js"></script>
    <link rel="stylesheet" href="style.css" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.7.0/p5.min.js"></script>
    <py-config>
        packages = ["proceso"]
    </py-config>
</head>

<body>
    <main></main>
    <py-script src="sketch.py"></py-script>
</body>

</html>

html,
body {
    margin: 0;
    padding: 0;
}

canvas {
    display: block;
}

Static Sketches#

Similar to Processing, proceso enables beginners to start programming with “static sketches” before introducing animation and interaction. The following example draws a few shapes and a flower on the screen.

from proceso import Sketch


p5 = Sketch()
p5.describe(
    "A rectangle, circle, triangle, and flower drawn in pink on a gray background."
)

# Create the canvas
p5.create_canvas(720, 400)
p5.background(200)

# Set colors
p5.fill(204, 101, 192, 127)
p5.stroke(127, 63, 120)

# A rectangle
p5.rect(40, 120, 120, 40)
# A circle
p5.circle(240, 240, 80)
# A triangle
p5.triangle(300, 100, 320, 100, 310, 80)

# A design for a simple flower
p5.translate(580, 200)
p5.no_stroke()
for _ in range(10):
    p5.ellipse(0, 30, 20, 80)
    p5.rotate(p5.PI / 5)

View sketch

Active Sketches#

proceso’s “active sketches” provide the run_sketch() method to handle initialization, looping, and events. The sketch below simulates the synchronization behavior observed in some species of fireflies.

from proceso import Sketch


p5 = Sketch()
p5.describe(
    "Ten white circles moving like fireflies on a dark blue background."
)

bugs = []
num_bugs = 10
coupling: object


def setup():
    p5.create_canvas(720, 400)
    global coupling
    coupling = p5.create_slider(0, 10, 5)
    for _ in range(num_bugs):
        bug = Bug()
        bugs.append(bug)


def draw():
    p5.background("midnightblue")

    for bug in bugs:
        bug.sync()

    for bug in bugs:
        bug.update()
        bug.check_edges()
        bug.draw()


class Bug:
    def __init__(self):
        self.x = p5.width * 0.5
        self.y = p5.height * 0.5
        self.r = 5
        self.angle = p5.random(p5.TWO_PI)
        self.da_dt = 1
        self.dt = 0.01
        self.freq = p5.random(5, 10)

    def draw(self):
        a = p5.remap(self.angle % p5.TWO_PI, 0, p5.TWO_PI, 0, 255)
        p5.fill(255, a)
        p5.stroke(255, a)
        p5.circle(self.x, self.y, 2 * self.r)

    def update(self):
        self.x += p5.cos(self.angle)
        self.y += p5.sin(self.angle)
        self.angle += self.da_dt * self.dt
        self.da_dt = 0

    def check_edges(self):
        if self.x > p5.width + self.r:
            self.x = -self.r
        if self.x < -self.r:
            self.x = p5.width + self.r
        if self.y > p5.height + self.r:
            self.y = -self.r
        if self.y < -self.r:
            self.y = p5.height + self.r

    def sync(self):
        K_N = coupling.value() / num_bugs
        self.da_dt = self.freq
        for bug in bugs:
            self.da_dt += K_N * p5.sin(bug.angle - self.angle)


p5.run_sketch(setup=setup, draw=draw)

View sketch

Coding Environment#

Cloud: PyScript (account required)#

PyScript is a great way to run proceso sketches with PyScript. Here is a project template.

Local: Anaconda + VS Code#

Here is one possible setup for running sketches on your local machine:

  1. Install the Anaconda Distribution of Python.

  2. Install Visual Studio Code.

  3. Get started with Anaconda Navigator and create a new Python environment with Python 3.10.

  4. Use the Navigator to open a terminal with your new Python environment and pip install proceso.

  5. Open VS Code and install the Microsoft Python extension to enable helpful features such as documentation, autocompletion, and so on.

  6. Select the interpreter created by your new Python environment.

  7. Add your HTML, CSS, and Python files and start coding.

  8. Open the terminal in VS Code and run python -m http.server to view your sketch in the browser.