Gamut Clamping

What is gamut clamping?

The HCT color space can represent colors that don't exist in sRGB (the color space displays use). When you set a high chroma at certain hue+tone combinations, the actual displayed color gets "clamped" to the nearest sRGB-representable color by Material Color Utilities.

For example: Hue 205° (blue), Chroma 72, Tone 61 → the sRGB gamut can only produce Chroma ~45 at that hue/tone. The extra chroma is silently lost.

How Systema handles it

The HCT Color Picker detects clamping by round-tripping: it converts your requested H/C/T to hex, then back to HCT, and compares all three channels. If any channel (Hue, Chroma, or Tone) differs by more than 0.5, a snap affordance appears overlaid on the right edge of the hex input — a Snap pill in the default editor layout, or a button showing the drifting channels (H:X C:Y) with a warning icon in the legacy standalone layout.

The tooltip lists the actual gamut-safe values, e.g. H:204.8 C:45.2 — that is the maximum the display can produce at your chosen hue and tone. There's no benefit to pushing past this point; the rendered result won't change.

Clicking the snap affordance writes only the drifted channels back to their gamut-safe (round-tripped) values, rounded to 0.1.

Practical implications

• High-chroma colors (vivid red, electric blue) clamp at lower tones (darker) and higher tones (lighter). Mid-tones allow the most chroma.
• Low-chroma colors (neutrals, pastels) rarely clamp.
• Gradient points at different hues may have different clamp ceilings. Systema shows clamping per gradient point independently.

---