Austin Rose
Projects/Reflected Glare Blocker

Reflected Glare Blocker

Live2025

Sightline geometry for blocking reflected window glare.

A sightline geometry calculator for an east-facing ground-floor window catching reflected afternoon sunlight off the neighbor's second-story window and wall, 18.5′ away. Given the height and distance of the reflection zone, it computes how tall a planter or tree needs to be at a given distance from the window to block the glare cone, with a height-vs-distance trade-off curve so the two variables can be tuned together.

Demo

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Why

The neighbor's second-story window across the way reflects late sun straight into a ground-floor window. The fix is some kind of obstacle (a planter, a tree) but the placement question is real: a shorter obstacle close to the window blocks the same cone as a taller one further out. I wanted to see the trade explicitly before committing to a tree species and a planting distance.

How

A React component with two views. The cross-section shows the sightlines from the top and bottom of the reflection source down through the obstacle to the critical point inside the window. The trade-off chart plots required obstacle height against distance from the window for full-block and partial-block cases, with a click-to-snap interaction so you can pick a configuration and see it reflected in the cross-section.

Lessons

For my specific measurements the answer landed at roughly a 15′ mature tree at 10.5′ from the house for full block, with a few zone 9b species suggestions to match. The deliverable wasn't the number; it was being able to see why the number was the number.

Built for this
  • Sightline geometry (top/bottom reflection-zone rays)
  • Height-vs-distance trade-off chart with click-to-snap
  • Coverage percentage and glare-cone subtended angle
Built on
  • Claude (artifact pair-authoring)
  • React, inline SVG