The Book of Shaders
Unknown
Free interactive guide by Patricio Gonzalez Vivo and Jen Lowe to writing GLSL fragment shaders, with live editable examples. Covers shaping functions, color, shapes, patterns, noise and fractal Brownian motion, teaching procedural image generation on the GPU.
More resources on Rendering
Blender Manual - Render
Official Blender reference for its render engines, Cycles path tracer and EEVEE real-time renderer, plus Workbench, color management and Freestyle. Explains sampling, light paths, denoising and render settings so users can configure and troubleshoot renders.
Upstairs (Architectural Representation)
A YouTube channel and learning platform on architectural representation, with tutorials on post-production and rendering in tools such as Blender, Twinmotion and Unreal Engine. Viewers learn to turn architectural models into clear, persuasive presentation images.
greyscalegorilla.com
Greyscalegorilla is a premier learning hub for Cinema 4D and related 3D workflows, offering tutorials, courses, and plugins that cover motion design, lighting, shading, and rendering. It provides a comprehensive library of training videos, project files, presets, textures, and practical resources for 3D artists.
PBR Book
The free online edition of Pharr, Jakob and Humphreys' Academy Award-winning text, presenting a complete physically based ray tracer alongside its theory. Readers learn light transport, sampling, materials and Monte Carlo integration well enough to build a production-quality renderer.
Blender Beginner Donut Tutorial (Blender 2.8)
Opening part of Andrew Price's step-by-step beginner series in which you build a donut scene from scratch. It covers the Blender interface, navigation, basic mesh modelling, sculpting, materials, lighting and rendering, leaving you able to produce a simple finished render.
LearnOpenGL
Free online book and tutorial series on modern OpenGL in C++, from creating a window and writing shaders through textures, transformations, cameras, lighting, model loading and advanced techniques such as shadow mapping, deferred shading and PBR. Readers can build a working real-time renderer.