CairoG2D/README.md
2026-08-15 10:47:17 +00:00

3.8 KiB

Cairo G2D — a 2D vector graphics engine in pure MQL5

Source code for the mql5.com article series Creating a Cairo-Inspired Graphics Library for MetaTrader 5.

Part 1: https://www.mql5.com/en/articles/23818

Part 2: https://www.mql5.com/en/articles/23993

A scanline rasteriser, path model and compositing pipeline written from scratch in MQL5, with no external libraries and no CCanvas. Everything it draws goes into one OBJ_BITMAP_LABEL, so a panel of a thousand shapes still costs the terminal exactly one chart object.


Which version do I want?

Use the release that matches the article you are reading. Each part of the series has its own release, frozen at the state the article explains — so if you are reading Part 1, the Part 1 release contains two header files and one demo, and nothing you have not read about yet.

Release Article What it adds
part-01 Part 1 — Why the Terminal Needs Its Own 2D Renderer Color.mqh, Surface.mqh — the ARGB type and the buffer-to-chart bridge
part-02 Part 2 — Points, Contours and the Path Path.mqh — points, contours, the path

Later parts are added to this table as they are published. The main branch is always the newest state, which will be ahead of every published article.


Installing

Download the release archive and extract it over your terminal's data folder (File → Open Data Folder in MetaTrader 5). The archive already has the right shape, so the files land where they belong:

MQL5/
├── Include/
│   └── CairoG2D/
│       ├── Color.mqh          the ARGB color type
│       ├── Surface.mqh        pixel buffer bound to one chart object
│       ├── Path.mqh           points, contours, the path
│       └── DemoTheme.mqh      the demos' shared palette - NOT library code
└── Experts/
    └── CairoG2D/
        ├── Article 01/
        │   └── Demo01_FirstPixels.mq5
        └── Article 02/
            └── Demo02_PathViewer.mq5

Then open the demo in MetaEditor, compile with F7, and drag it onto any chart. It needs no inputs, no indicators and no market data.

The library headers are included the usual way:

#include <CairoG2D/Color.mqh>
#include <CairoG2D/Surface.mqh>

DemoTheme.mqh is deliberately shipped alongside them but is not part of the engine. It holds the light palette and the chart setup that make every screenshot in the series look the same, and nothing in the renderer depends on it.


Scope

This is a software rasteriser aimed at interface redraw — panels that are repainted when something happens, not scenes animated at a high frame rate. It uses straight (non-premultiplied) alpha from input to output, which is what COLOR_FORMAT_ARGB_NORMALIZE expects.


Removing it

Each demo draws into a single chart object and deletes that object on OnDeinit, so removing the Expert Advisor leaves the chart exactly as it was found. Nothing is written outside the terminal's data folder.


Copyright 2026, Sandro Begashvili

You are free to use this code in your own projects and to extend it, commercially or otherwise. The only thing asked in return is attribution: keep a mention of the author's mql5.com profile in the source you derive from it.

If you build something with it, I would genuinely like to see it — the Telegram link above is the fastest way to reach me.