Source: https://mokxi.com/libraries/adafruit-gfx Updated: 2026-11-02 Libraries / Displays Arduino library · Displays # Adafruit GFX: the drawing calls behind every Adafruit display Adafruit GFX is not a display driver on its own. It is the layer the Adafruit display libraries (SSD1306, SH110X, ILI9341, ST7735, ST7789, PCD8544 and the rest) are built on: each driver says how to light one pixel, and GFX supplies everything else, from lines and filled circles to text, custom fonts, bitmaps and screen rotation. Learn its calls once and they work on a monochrome OLED and a color TFT alike. Open the example in the editor See the calls Built in on Mokxi: #include and it builds, with nothing to install. Free, and no account needed. ## What Adafruit GFX Library does Coordinates start at the top left corner, x to the right and y down. Colors are whatever the display understands: on a one-color OLED they are on, off or inverse, and on a color TFT they are 16-bit RGB565 values, which a driver builds for you with color565(r, g, b). The detail that catches people is text placement. With the built-in font, setCursor() names the top left of the first character. With a custom GFXfont loaded by setFont(), it names the baseline, so text placed at y = 0 is drawn almost entirely above the screen and vanishes. Library Manager name | Adafruit GFX Library Author | Adafruit Include | #include #include Boards | every board Mokxi compiles for but ATtiny85 In the simulator | Runs, with a gap the note below names. Parts it drives | OLED display, 128x64, TFT display, 240x320 ## Install it It builds on every board Mokxi compiles for but ATtiny85. In Mokxi it is built in: #include and the sketch compiles, with no download, no zip and no Library Manager. On a real board, install "Adafruit GFX Library" by Adafruit from the Arduino IDE’s Library Manager (Sketch, Include Library, Manage Libraries), or add Adafruit GFX Library to lib_deps in PlatformIO. Mokxi follows the calls of release 1.11.11, so a sketch written here builds there too. What to know in the simulator: The Fonts/ headers (FreeSans9pt7b and the rest) draw Mokxi’s own characters at each font’s size, not the GNU FreeFont typefaces; a fontconvert font of the sketch’s own draws as upstream. Characters below 32 and above 126 draw blank. ESP32-C3 · Arduino Uno · Arduino Nano · Arduino Mega 2560 · Arduino Leonardo · SparkFun Pro Micro · Arduino Micro · ESP32-C6 · Raspberry Pi Pico · Raspberry Pi Pico W · Seeed XIAO SAMD21 · STM32 · STM32 Nucleo-F411RE · STM32 Blue Pill · micro:bit V2 · Arduino Uno R4 · ESP32 DevKit · ESP32-S3-DevKitC-1 · ESP8266 NodeMCU · Arduino Pro Mini 3.3 V · Seeed XIAO ESP32-C3 · ESP32-C3 SuperMini · Seeed XIAO ESP32-C6 · ESP32-DevKitC V4 · LOLIN32 Lite · Wemos D1 R32 · Cheap Yellow Display · TTGO T-Display · Seeed XIAO ESP32-S3 · Arduino Nano ESP32 · Arduino Nano RP2040 Connect · Seeed XIAO RP2040 · Waveshare RP2040-Zero · Arduino Uno R4 WiFi ## The calls you will use In the order a sketch meets them. ### display.setRotation(1) Turns the coordinate system in steps of 90 degrees (0 to 3). width() and height() swap to match, so code that reads them keeps working in landscape. ### display.fillScreen(0) Fills the whole screen with one color. On a TFT that is the slowest call there is, so clear only what changed when you can. ### display.drawLine(x0, y0, x1, y1, color) Draws a straight line between two points. drawFastHLine() and drawFastVLine() are quicker for lines that are flat or upright. ### display.fillRoundRect(x, y, w, h, r, color) A filled rectangle with corners of radius r, the usual shape for a button. drawRect(), fillRect(), drawRoundRect() and drawTriangle() are its relatives. ### display.drawCircle(x, y, r, color) An outlined circle around the center point; fillCircle() draws a solid one and drawEllipse() an oval. ### display.setFont(&FreeSans9pt7b) Switches print() to a GFXfont from the Fonts folder (include its header first). setFont() with no argument goes back to the built-in 6 by 8 font. ### display.getTextBounds("Hello", 0, 20, &x1, &y1, &w, &h) Works out the box a string would cover without drawing it, which is how you center text: subtract w / 2 from the middle of the screen. ### display.drawBitmap(x, y, icon, 16, 16, color) Draws a one-bit picture from a byte array. drawRGBBitmap() takes an array of RGB565 pixels for a color screen. ### GFXcanvas1 canvas(128, 32) An off-screen drawing surface in RAM with every GFX call. Draw a frame into it, then copy it out with drawBitmap(x, y, canvas.getBuffer(), 128, 32, color) to avoid flicker. ## Example: Grove OLED On the Arduino Mega 2560 R3. It runs in the browser exactly as printed. sketch.ino · Arduino Mega 2560 R3 Open it in the editor, wired and ready to run · Grove OLED: the project page ## Common errors and how to fix them ### fatal error: Adafruit_I2CDevice.h: No such file or directory Since version 1.10, Adafruit GFX depends on Adafruit BusIO. Install it from the Library Manager (choose Install all when it asks about dependencies), then compile again. ### Text with a custom font is cut off or missing at the top of the screen A GFXfont is drawn from its baseline. Move the cursor down by about the font height, for example setCursor(0, 14) for a 9 point font, or measure it with getTextBounds(). ### New numbers draw on top of old ones and turn into a blur Drawing never erases. With the built-in font, setTextColor(foreground, background) paints the whole character cell. Custom fonts draw no background, so fillRect() over the old value first. ## Questions and answers ### Are the Fonts folder typefaces the real FreeSans and FreeMono on Mokxi? No. The font headers build and set the size, but on Mokxi they draw Mokxi’s own characters scaled to that size, so text lands where your sketch puts it in a different typeface. A font you made yourself with fontconvert is drawn from its own bitmaps. ## Projects that use Adafruit GFX Library Built-in projects that include it. Each page has the full sketch and opens in the editor, already wired. Heartbeat monitor A Pulse Sensor on a fingertip, PulseSensor Playground finding the beats, and an OLED drawing the wave scrolling by with the heart rate over it. Mixbox-style controller on a Pico W A S D directions for the left hand and eight lit buttons for the right, on GP2040-CE’s Pico pins, with SOCD modes, turbo and an OLED input display. Fight stick on a Pico A Sanwa-style lever and eight lit buttons on GP2040-CE’s Pico pins, with SOCD and stick modes on button combos, turbo and an OLED that draws the lever as you move it. Breakout game on an OLED Breakout game on an OLED with a knob for the paddle: 32 bricks, three lives, a faster ball for every wall you clear, and sound on a piezo. Leverless controller on a Pico A full leverless build on GP2040-CE’s Pico pins: SOCD and D-pad or stick modes on button combos, turbo, lit buttons that react to every press and an OLED input display. Touch paint Draw on a 2.8 inch TFT with its resistive touch panel: two SPI chips on one module, and the raw touch counts mapped to pixels. ## Keep going ### Learn - Arduino OLED Display (SSD1306) Tutorial - Arduino ILI9341 TFT Display: Wiring and Code ### Parts - OLED display, 128x64 - TFT display, 240x320 ### More displays libraries - Adafruit SSD1306 - LiquidCrystal I2C - LiquidCrystal - LCD_I2C - hd44780 - TFT_eSPI - U8g2 - U8glib Every built-in library · Open the editor ## Try Adafruit GFX Library without installing anything Open the example, change the sketch, and keep your version in a free account. Start building free Open the editor