Dot Topography – Image-Based Halftone Density System | TouchDesigner Tutorial

video description · xtal members only* in this tutorial, we build a dot-based halftone system in touchdesigner that translates image brightness into spatial density. rather than applying a simple post-effect, this setup reconstructs the input image as a structured field of dots, where form emerges from resolution, instancing, and data-driven control. the core idea is to treat the image not as pixels, but as information. brightness values are analyzed, remapped, and used to control dot placement, scale, and distribution inside a geometry-based rendering pipeline. through this process, the image becomes a kind of topography. high-density areas compress into tight dot clusters, while lighter regions open up and breathe, creating a visual rhythm that feels both graphic and organic. what you’ll learn in this tutorial - how to prepare and normalize image input for data-driven systems - using resolution, fit, and level operators to control image scale and contrast - generating positional data from ramps and math operators - reordering channels to build custom xy coordinate maps - driving geometry instancing using image-derived data - controlling dot scale and density through render resolution - improving dot clarity by increasing render resolution instead of post-sharpening this system is designed to be flexible. by changing the input image, resolution values, or ramp shapes, you can quickly explore a wide range of halftone styles — from clean print-like dots to noisy, dense textures. i recommend experimenting slowly. try pushing the resolution higher, exaggerating contrast, or breaking the balance on purpose to discover unexpected results. this approach works especially well for: graphic visuals, experimental motion, print-inspired textures, and image-based abstractions. thanks for watching, and feel free to adapt this structure into your own visual language. — xtal