Inside the 60 FPS WebGL Floor Slicing Shader & PostGIS Entity Resolution Pipeline

Rendering hundreds of multi-story buildings with individual floor plates at 60 frames per second in the browser—without duplicating geometry for every floor—required custom GPU shader engineering and a deterministic geospatial pipeline.

1. Custom GLSL FloorSliceExtension

Instead of generating separate polygon meshes for each floor of a 16-story building, we extrude each building footprint once and inject a custom Deck.gl LayerExtension into the vertex and fragment shaders:

• Procedural Floor Lines: Using mod(vPosition.z, 3.2), the fragment shader darkens horizontal bands every 3.2 meters to delineate individual stories.
• Zero-Allocation Floor Slicing: When you drag the Floor Slicing slider, the uniform uSliceElevation updates on the GPU and executes if (vPosition.z > uSliceElevation) discard;—slicing the entire city horizontally at 60 FPS with zero CPU buffer re-uploads.
• Interactive Floor Highlight: Hovering or clicking a specific elevation illuminates that 3.2m slab (uSelectedFloor) in electric cyan.

2. Multi-Tier Address Entity Resolution

Classified listings on verified regional portals rarely include exact GPS coordinates; instead, agents write free-form Russian or Kyrgyz addresses such as "мкр Асанбай 28, ориентир Томми Молл". Our Python FastAPI crawler resolves these descriptions into PostGIS building_id foreign keys using:

1. Normalized street and microdistrict dictionary matching.
2. Trigram similarity (pg_trgm) and building series validation (104, 105, 106, monolith).
3. Geodesic proximity verification against known landmark POIs.