[FIXED] How Do I Arch Text In Reportlab

Issue

text = 'Hello World'
length = len(text)
can.translate(400, 293)
can.rotate(-1 * 200 / 1.06)
can.rotate(-1 * (200 / length) / 1.06)
for n in text:
    can.rotate(200 / length)
    can.translate(0, -1 * 0.8*inch)        
    can.drawString(0, 0, n)

Here is what I have tried. The text is arched however the letters are rotated. What is the correct way to do this?

Here is what I would like the text to look like.

Solution

It would probably be easier if you would use an easier formula to draw your letters. Since you rotate + translate your letters at the same time it can be tough to rotate the letters back vertically.

Using cosinus and sinus seems to be a good idea since you want to draw your letters in a circle without the use of rotate.

here is an example:

from reportlab.pdfgen import canvas
import numpy as np

can = canvas.Canvas("rl-hello_again.pdf", pagesize=(595.27, 841.89))
text = 'Hello World'
length = len(text)
can.translate(400, 293)
degrees_perletter = 180 / length
i = 0
for n in text:
    x = np.sin(np.radians(degrees_perletter * i)) * 20
    y = np.cos(np.radians(degrees_perletter * i)) * 20
    can.translate(x, y)
    can.drawString(0, 0, n)
    i += 1

can.showPage()
can.save()

In a second step if you want to rotate the letters. Then i advise to only rotate the letter after the translation and in a second step rotate the letter back to its vertical position. Like this its easier to not get lost between rotations and translations.

See code below:

from reportlab.pdfgen import canvas
import numpy as np

can = canvas.Canvas("rl-hello_again.pdf", pagesize=(595.27, 841.89))
text = 'Hello World'
length = len(text)
can.translate(400, 293)
degrees_perletter = 180 / (length+2)
i = 1
for n in text:
    x = np.sin(np.radians(degrees_perletter * i)) * 20
    y = np.cos(np.radians(degrees_perletter * i)) * 20
    degrees_l=-degrees_perletter*i+90
    can.translate(x, y)
    can.rotate(degrees_l)
    can.drawString(0, 0, n)
    can.rotate(-degrees_l)
    i += 1

can.showPage()
can.save()

Answered By - tetris programming