Salvo

Overview

Salvo is a display-fireworks and pyrotechnic-production theme for event design firms — corporate galas, weddings, municipal celebrations, concert pyrotechnics, and private events. The persistent background isn’t a decorative shader wash: it’s a real-time particle-physics firework simulation, and every interactive tool on the site runs on real pyrotechnic industry math.

1. A real NFPA 1123 minimum-distance calculator. Enter a shell size and it computes minimum spectator distance and minimum mortar-to-structure setback from the actual published formula (70 ft × shell diameter, 100 ft floor), plus a separately-labelled “conservative planning” figure using the widely-cited 100 ft/inch industry rule of thumb — the two are never conflated. PHP and JS implementations match exactly.

2. A real 71-cue choreography timeline. A hand-composed finale sequence — opening salvo, two build sections, a ground-effects interlude, a final build, and an escalating finale barrage — modeled on how real firing software exports a cue list, rendered as a scrollable timeline driven by one shared data array (localized once from PHP, never duplicated).

3. A real star-chemistry reference. The actual metal-salt colorants behind every firework color — strontium red, barium green, copper blue, sodium gold — with approximate flame temperatures and the real reason there’s no single-element purple and why aluminum/titanium “colors” are incandescence, not atomic emission.

The signature GPU background is a hand-written, zero-dependency WebGL2 particle simulation: shells launch on real ballistic trajectories (v0 = √(2g·burst-height), so every shell reaches apex exactly at its intended burst altitude), burst into 70-150 stars per shell across five real shell types (peony, chrysanthemum with glitter trails, willow, crossette with a real mid-flight secondary split, and a ring-pattern shell), and each star’s color genuinely cools from its chemical emission color to an ember-orange afterglow as it burns out. Shell density scales with scroll position — sparse over the hero, a full barrage by the footer. Reduced-motion, no-WebGL2, weak-GPU, and save-data visitors get a clean CSS night-sky gradient, no canvas touched at all. 10 demo show case studies across all five event types with real sourced fireworks photography.