Sunlight Analysis | Wrengler Documentation

Sunlight Hours computes how many hours of direct sun reach a surface over a chosen period, and paints the result as a live heatmap on your geometry.

How it Works

From each tested point, the study casts a ray toward the sun's position at intervals across the period and counts the ones that arrive unobstructed. Context geometry in your group or selection does the blocking. The reference implementation is verified against closed-form solar physics, and faster backends are checked against it, so the answer doesn't depend on your hardware.

Running an Analysis

Set up geometry — organize target surfaces and surrounding context into a group, or select them in Rhino.
Open the Sun tab in the Wrengler panel.
Set parameters — location (sync from Rhino or set manually), date range (a single day or a season), and time resolution (the interval between sun positions, e.g. 15 minutes).
Run — the heatmap appears on your geometry in the viewport.

Live Mode

With Live Mode enabled, the engine stays active in the background: change building heights or setbacks and the heatmap follows.

💡

Use Live Mode during early massing to read the solar consequence of a move as you make it, rather than waiting on a bake.

Performance Tips

Grid resolution — finer grids give smoother heatmaps but cost more compute. Start medium for live feedback.
Context complexity — on large urban models, keep the group focused on geometry that actually shades your target.