Sub-pixel Distance Transform: A Breakthrough in High-Quality Font Rendering for WebGPU

This article delves into the challenges and solutions for achieving high-quality font rendering in WebGPU. Addressing shortcomings in existing Signed Distance Fields (SDFs) generation methods, the author presents a novel sub-pixel accurate distance transform algorithm (ESDT). ESDT cleverly combines CPU and GPU strengths, employing an improved Euclidean Distance Transform to effectively solve the deviations encountered in traditional methods when handling sub-pixel accuracy and grayscale pixels. The result is precise rendering of various fonts, including emojis, significantly enhancing font rendering quality.