Rendering crisp vector text on modern GPUs is deceptively difficult. Traditional approaches sidestep the problem by rasterizing glyphs on the CPU into texture atlases. However, this approach degrades quickly when scaling dynamically, rotating across 3D planes, or dealing with constantly shifting dynamic text.
Signed Distance Field (SDF) and Multi-channel Signed Distance Field (MSDF) techniques partially solved this by storing vector proximity rather than raw pixels. While MSDF preserves sharp corners by isolating direction vectors into multiple channels, it still consumes significant texture memory and blurs under extreme magnification.
The Slug algorithm shifts the paradigm by eliminating texture atlases entirely. Instead of sampling precomputed distance fields, Slug encodes quadratic and cubic Bezier outlines directly into GPU memory buffers. The fragment shader evaluates glyph winding rules and ray crossings in real time on the hardware. This produces pixel-perfect outlines with zero antialiasing artifacts at any scale.
Moving mathematical evaluation directly into the fragment shader removes memory caching trade-offs. It shows how revisiting fundamental rendering models can outpace decades of texture-caching heuristics.














