Module gradient 

Constants

GRADIENT_COOL

Multi-stop gradient for cool tones (White Balance slider, scope backgrounds). #0A1A25 (deep river) → #1A3A45 (deep water) → #4D8A8A (teal) → #6DAEAE (mist) → #E8E4D9 (parchment).

GRADIENT_WARM

Multi-stop gradient for warm tones (Exposure slider, progress bars, borders). #1A0505 (deep soil) → #3A1A15 (dark bark) → #6B3A2A (amber shadow) → #B57A35 (warm amber) → #E8A035 (golden amber).

Functions

gradient_horizontal

Pre-compute a horizontal row of gradient colors.

lerp_color

Linear interpolation between two RGB colors. t=0 returns a, t=1 returns b. t is clamped to [0, 1]. If either color is not Color::Rgb, returns a unchanged.

multi_stop_color

Interpolate across a multi-stop gradient at position t (0.0 — 1.0).