Diwali Diya in Python Turtle

Advanced · Festivals · 78 lines · draws in about 11 seconds

This program draws a glowing clay diya for Diwali, with an oval bowl worked out using sine and cosine and a flame made of three teardrops.

Diwali Diya in Python Turtle: the finished drawing

import math

import turtle

screen = turtle.Screen()

screen.title("Diwali Diya")

screen.bgcolor("#1b0d2a")

t = turtle.Turtle()

t.speed(5)

def oval(x, y, width, height, color, start=0, end=360):

"""Fill an oval centred at (x, y), or the part of it from angle start to angle end."""

points = []

for angle in range(start, end + 1, 5):

a = math.radians(angle)

points.append((x + width / 2 * math.cos(a), y + height / 2 * math.sin(a)))

t.penup()

t.goto(points[0])

t.pendown()

t.color(color)

t.begin_fill()

for point in points:

t.goto(point)

t.end_fill()

def flame(x, y, radius, height, color):

"""A teardrop: a round bottom centred at (x, y) and a point `height` above it."""

lean = math.degrees(math.asin(radius / height))

side = math.sqrt(height ** 2 - radius ** 2)

t.penup()

t.goto(x, y + height)

t.setheading(270 + lean)

t.pendown()

t.color(color)

t.begin_fill()

t.forward(side)

t.circle(-radius, 180 + 2 * lean)

t.forward(side)

t.end_fill()

# A warm glow: big dots, darkest on the outside

t.penup()

t.goto(0, 10)

for size, color in [(380, "#2a1236"), (300, "#3d1838"), (220, "#5a2234"), (150, "#7a2e2a")]:

t.dot(size, color)

# The clay lamp: a foot, a round bowl and the rim with oil inside

oval(0, -150, 110, 36, "#8a3212")

oval(0, -60, 280, 180, "#b5441b", 180, 360)

oval(0, -60, 280, 56, "#e07b39")

oval(0, -56, 236, 36, "#5c1d06")

# Gold dots painted round the bowl

t.penup()

for angle in range(205, 340, 15):

a = math.radians(angle)

t.goto(105 * math.cos(a), -70 + 60 * math.sin(a))

t.dot(12, "gold")

# The wick

t.goto(0, -58)

t.setheading(90)

t.pendown()

t.pensize(5)

t.color("#2b1a10")

t.forward(26)

t.pensize(1)

# Three flames inside each other: orange, gold, then pale yellow

flame(0, -4, 34, 120, "darkorange")

flame(0, -10, 23, 84, "gold")

flame(0, -16, 12, 46, "lightyellow")

t.hideturtle()

turtle.done()

Open in the editor

How the code works

Ovals from points

Turtle has no oval command, so oval() works out points with math.cos() and math.sin(), stretching a circle to the width and height it is given. With start=180 and end=360 it draws only the bottom half, which becomes the bowl.

def oval(x, y, width, height, color, start=0, end=360):
    """Fill an oval centred at (x, y), or the part of it from angle start to angle end."""
    points = []
    for angle in range(start, end + 1, 5):
        a = math.radians(angle)
        points.append((x + width / 2 * math.cos(a), y + height / 2 * math.sin(a)))
    t.penup()
    t.goto(points[0])
    t.pendown()
    t.color(color)
    t.begin_fill()
    for point in points:
        t.goto(point)
    t.end_fill()

A teardrop flame

A flame is a straight side down to a round bottom, circle() round the bottom, and a straight side back up to the tip. math.asin() finds the angle at which the straight sides meet the round part smoothly.

def flame(x, y, radius, height, color):
    """A teardrop: a round bottom centred at (x, y) and a point `height` above it."""
    lean = math.degrees(math.asin(radius / height))
    side = math.sqrt(height ** 2 - radius ** 2)
    t.penup()
    t.goto(x, y + height)
    t.setheading(270 + lean)
    t.pendown()
    t.color(color)
    t.begin_fill()
    t.forward(side)
    t.circle(-radius, 180 + 2 * lean)
    t.forward(side)
    t.end_fill()

A glow from big dots

Four dots, drawn from the biggest and darkest to the smallest and warmest, look like light spreading out from the flame.

for size, color in [(380, "#2a1236"), (300, "#3d1838"), (220, "#5a2234"), (150, "#7a2e2a")]:
    t.dot(size, color)

Three flames, one inside another

Drawing a smaller, paler flame on top of a bigger one gives the flame a hot, bright centre.

flame(0, -4, 34, 120, "darkorange")
flame(0, -10, 23, 84, "gold")
flame(0, -16, 12, 46, "lightyellow")

Make it yours

Change the code above and press Run. Some ideas:

Add a fifth glow ring by putting (450, "#22102f") at the front of the glow list.
Change range(205, 340, 15) to range(205, 340, 30) for fewer gold dots, further apart.
Change "darkorange" to "orangered" for a redder flame.

What it uses

Every turtle command the site supports is listed on Python turtle online.