Rare Earth Juejin Tech Community

Jul 9, 2025 · Frontend Development

Create a Red Screen with GLSL: A Simple Four‑Line Fragment Shader Tutorial

This article walks through the fundamentals of GLSL fragment shaders, comparing them to Canvas 2D drawing, explaining gl_FragColor, and providing step‑by‑step code examples for solid colors, linear and radial gradients, glowing rings, and diagonal line effects, all illustrated with images.