grafix

A bare metal C++ graphics library for driving 0.96" SSD1306 OLED displays (128x64) using Arduino. This library was implemented from scratch based on the SSD1306 datasheet to provide a minimal driver without relying on general purpose graphics frameworks like Adafruit GFX.

What does it implement ?

• SSD1306 initialization sequence and page addressing mode.
• Buffer Management of the 1KB framebuffer (128x64 bits) for rendering.
• Pixel plotting and line drawing using Bresenham's algorithm.
• Relies only on the standard Arduino Wire library for I2C communication.

Hardware Requirements

• Microcontroller: Arduino Uno, Mega, or compatible AVR boards.
• Display: 0.96" OLED Display (Driver: SSD1306, Resolution: 128x64).
• Interface: I2C (Address: 0x3C).

Pinout (Arduino Uno)

• VCC: 5V or 3.3V
• GND: GND
• SDA: A4
• SCL: A5

Installation & Setup (PlatformIO)

Library is structured to be used within a PlatformIO environment.

1. Clone or download this repository.
2. Add the library to your project's platformio.ini. If you are developing locally, you can reference the library path directly:

[env:uno]
platform = atmelavr
board = uno
framework = arduino
; Adjust the path relative to your project location
lib_deps = file:///path/to/Grafix

Basic Usage

Include the header and instantiate the Grafix class. Note that display() must be called to send the buffer to the screen.

#include "grafix.h"

// Initialize I2C and OLED
display.begin();

// Clear existing buffer
display.clear();

// Draw operations
display.drawPixel(10, 10, 1);
display.drawLine(0, 0, 127, 63, 1);

// Push buffer to display
display.display();

Running the Examples

There are examples demonstrating the library's capabilities.

3D Cube Wireframe

This example renders a rotating 3D cube using a software based projection pipeline (rotation matrices and perspective projection) mapped to the 2D display.

1. Navigate to the example directory:

   cd examples/threedcube

2. The platformio.ini in this folder is pre configured to link to the library root.
3. Compile and upload:

   pio run -t upload

Implementation Status and ToDo's

Implemented:

• I2C Communication & Initialization
• Framebuffer management (clear, display)
• drawPixel
• drawLine (Bresenham's Algorithm)

Planned / In-Progress:

• drawRect / fillRect
• Text Rendering Engine (setCursor, print)
• Brightness Control (setBrightness)
• Pomodoro Timer Example