A new C++ library called Canvas_ity delivers a single-header, HTML5 canvas-like 2D rasterizer designed for immediate-mode vector graphics rendering. The library prioritizes high-quality rendering, ease of use, and compact size while supporting nearly all W3C HTML5 2D canvas features except hit regions and property getters.

Canvas_ity implements gamma-correct blending and bicubic convolution resampling for superior visual quality, with trapezoidal area antialiasing that smooths even nearly horizontal or vertical lines. The API closely mirrors the HTML5 canvas specification but adapts surface-level calls for C++ idioms, avoiding strings and auxiliary classes. Developers can compare the C++ implementation against browser canvas outputs using the included automated test suite.

The library includes a comprehensive example demonstrating path building, fills, strokes, line dash patterns, gradients, drop shadows, and compositing operations. A complete 256x256 star rendering program shows how to output TGA image files, with the C++ code mapping nearly one-to-one with its JavaScript equivalent. With 459 GitHub stars and 32 forks, Canvas_ity offers developers a lightweight alternative for 2D graphics rendering that maintains visual fidelity while staying true to the familiar canvas API.