Scaled Text

The framebuf module built into micropython only supports an 8x8 font, which can be rather small. While it's possible to use another extension (eg. X-GLCD Font) to load and use larger fonts, you'll need a font file for every font size, and the extension will consume additional memory.

The Scaled Text extension allows you to draw larger fonts by scaling the built-in 8x8 font. You can scale it to any size, without requiring any added font files. The drawback is that the text will look blocky at larger sizes.

The scaled text extension can work with the SSD-1306, ILI9341, or ST7789 displays.

Wiring

In the below example, we are using the SSD1306, but other types of displays can also be used.

Code

This code will draw text on screen at two different sizes.

Blocks

Python

import machine
import ssd1306
import scaled_text

i2c0 = machine.I2C(0, freq=100000)
ssd1306_i2c = ssd1306.SSD1306_I2C(128, 64, i2c0, 60)
ssd1306_i2c.init_display()
text_scaler = scaled_text.ScaledText(ssd1306_i2c, fb_type=scaled_text.SSD1306)
ssd1306_i2c.fill(0)
text_scaler.text('Hello', 0, 0, 1, scale=2)
text_scaler.text('World', 0, 20, 1, scale=4)
ssd1306_i2c.show()

Results

You should see "Hello" printed in 2x sized font, and "World" in 4x sized font.

`class ScaledText` - draw text with scaled version of the built-in font

Constructors

scaled_text.ScaledText(fb, fb_type=SSD1306)

Creates an ScaledText object.

The arguments are:

fb An object representing the screen device.
fb_type The type of screen device, which can be one of the following:
- scaled_text.SSD1306 For SSD1306 and SH1106.
- scaled_text.ILI9341 For ILI9341 display (used in the ESP32 CYD).
- scaled_text.ST7789 For ST7789 display.

Returns an ScaledText object.

Methods

ScaledText.text(s, x, y, c=1, scale=2, background=None):

Draws the specified text.

Depending on your display device, you may need to perform a show() after drawing the text.