drawingLib.py

import time
import threading
import writeYourProgram as _w
from typing import Literal, Sequence

# Do not import tkinter at the top-level. Someone with no installation of tkinter should
# be able to user WYPP without drawing support.

@_w.record
class Size:
    width: float
    height: float

@_w.record
class Point:
    x: float
    y: float

type ShapeKind = Literal['ellipsis', 'rectangle']

type Color = Literal['red', 'green', 'blue', 'yellow', 'black', 'white']

@_w.record
class FixedShape:
    shape: ShapeKind
    color: Color
    size: Size
    position: Point

# coordinate system: origin is in the upper left corner
def _transformPoint(p, windowSize: Size):
    return (p[0] * 100 + windowSize.width/2, p[1] * -100 + windowSize.height/2)

def _renderFixedShape(prim: FixedShape, windowSize: Size, canvas):
    sz = prim.size
    pos = prim.position
    coords = [
        (pos.x - sz.width/2, pos.y - sz.height/2),
        (pos.x + sz.width/2, pos.y - sz.height/2),
        (pos.x + sz.width/2, pos.y + sz.height/2),
        (pos.x - sz.width/2, pos.y + sz.height/2)
    ]
    coords = [_transformPoint(p, windowSize) for p in coords]
    color = prim.color
    if prim.shape == 'rectangle':
        canvas.create_polygon(coords, fill=color, outline=color)
    elif prim.shape == 'ellipsis':
        upperLeft = coords[0]
        lowerRight = coords[2]
        canvas.create_oval(
            upperLeft[0], upperLeft[1],
            lowerRight[0], lowerRight[1],
            fill=color,
            outline=color
        )

def _drawCoordinateSystem(canvas, windowSize: Size):
    x = windowSize.width / 2
    y = windowSize.height / 2
    canvas.create_line(x, 0, x, windowSize.height, dash=(4,2))
    canvas.create_line(0, y, windowSize.width, y, dash=(4,2))

def drawFixedShapes(shapes: Sequence[FixedShape],
                    withCoordinateSystem=False,
                    stopAfter=None) -> None:
    try:
        from tkinter import Tk, Frame, Canvas, BOTH
    except ImportError:
        import sys
        sys.stderr.write("Could not import tkinter. Please install the tkinter library.")
        raise
    class _WyppFrame(Frame):
        def __init__(self, diags, windowSize, withCoordinateSystem):
            super().__init__()
            self.master.title("Write Your Python Program")
            self.pack(fill=BOTH, expand=1)
            canvas = Canvas(self)
            if withCoordinateSystem:
                _drawCoordinateSystem(canvas, windowSize)
            for d in diags:
                _renderFixedShape(d, windowSize, canvas)
            canvas.pack(fill=BOTH, expand=1)
    root = Tk()
    winWidth = 800
    winHeight = 800
    ex = _WyppFrame(shapes, Size(winWidth, winHeight), withCoordinateSystem)
    root.geometry(f"{winWidth}x{winHeight}+50+50")
    root.lift()
    # bring window to front
    root.attributes('-topmost',True)
    root.after_idle(root.attributes,'-topmost',False)
    if stopAfter:
        def close():
            time.sleep(stopAfter)
            print('Closing drawing window automatically ...')
            root.destroy()
        t = threading.Thread(target=close, daemon=True)
        t.start()
    root.mainloop()