带NPC和巨龙的可破坏体素中世纪王国

Build a large medieval voxel kingdom that runs in the browser, ideally as a single self-contained HTML file with a WebGL engine such as Three.js. Generate a terrain of grass, farmland patches in yellow and green, a winding river and a snowy mountain range on the horizon. At the centre place a walled castle city in concentric rings, with a keep, a church with a spire, and hundreds of houses with red, blue and yellow roofs; every building should have a purpose and an interior. Populate it with soldiers and townsfolk who have jobs and react to an invasion, include siege equipment, a fire-breathing dragon and voxel-level destruction. Add a free-flying camera that can move through the streets and rise over the whole map, plus a small side panel of settings sliders. Aim for millions of voxels at a smooth frame rate. Done means the kingdom loads, the camera can roam freely, characters move around, and buildings can be destroyed.