Module border 

Constants

PANEL_ACHIEVEMENT_CYCLE

PANEL_ACHIEVEMENT_TINT

PANEL_PURCHASE_CYCLE

PANEL_PURCHASE_TINT

Tint constants exported so callers (sidebar, upgrades, achievements) can request a matching panel-border flash without redefining the palette. Same values the HUD title border uses for those events, so HUD + panel always pulse in the same hue.

PANEL_UNAFFORDABLE_CYCLE

PANEL_UNAFFORDABLE_TINT

Functions

draw_animated

paint_border_flash

Recolor the rectangular border of area by walking it cell-by-cell with the same wave-tint logic as draw_animated, but driven by a single (tint, strength) pair. Used to flash secondary panel borders (Fingerers / Upgrades sidebar) on purchase events so the whole panel reads as “something just happened here”, not just the row that changed.

plateau_fade

1.0 for the bulk of the flash, smoothstep-decays only in the last ~40%. Shapes like: —[=============___].