Algorithms for visual effects and animation on the ZX Spectrum

This section is dedicated to graphics programming techniques, visual effects algorithms, and animation methods used to create impressive graphics, 3D scenes, and demo productions on the ZX Spectrum. It brings together articles covering the mathematical foundations of computer graphics, Z80 optimization techniques, and practical implementations of effects that became hallmarks of the Spectrum demoscene.

The collection covers topics ranging from basic point, line, and circle drawing algorithms to advanced rendering systems featuring texture mapping, shading, and 3D transformations. Articles explore 3D object rendering, perspective projection, raycasting, voxel graphics, Z-buffering, Gouraud and Phong shading, as well as techniques for accelerating mathematical calculations on the ZX Spectrum.

A major part of the section focuses on classic demoscene effects, including rotators, rotozoomers, tunnels, plasma, fire, water simulations, image morphing, attribute effects, scrollers, border effects, and various screen transition techniques. Both well-known effects from famous demos and original experimental implementations are covered.

Additional articles discuss color processing and image generation techniques such as dithering, pseudo-color rendering, palette expansion, image smoothing, graphics conversion, color video playback, and methods for overcoming the limitations of the standard Spectrum display hardware. Topics also include animation packing, data compression, bitplane graphics, and display optimization.

The section contains practical tutorials on graphics mode programming, game engine development, texture mapping, fractal generation, spline mathematics, sine-based effects, and many other algorithms used in advanced visual productions of the era.

Articles (115)