Engine stage: background

Modal

Parameter	Default	Range	What it does
bg_hue	0	0 – 1	Where the backdrop starts in the preset’s palette, as a coordinate along it.
bg_bright	0	0 – 1	How lit the backdrop is; 0 is black and the scene draws on nothing.
bg_vignette	0	0 – 1	Darkens the backdrop toward the corners, pulling the eye to the middle.
bg_angle	0	0 – 1	Direction the backdrop ramp runs in, as a fraction of a full turn.
bg_hue_span	0	-0.5 – 0.5	How far along the palette the ramp travels from bg_hue; 0 is a flat colour.
bg_shade	0.72	0 – 1	Brightness multiplier at the ramp’s start, so a sky can be dark at one edge.
bg_shade_end	1	0 – 1	Brightness multiplier at the ramp’s far end.
bg_ramp_gamma	1	0.25 – 4	Bends the ramp’s progress: below 1 the far colour arrives early, above 1 it holds off.
bg_band_amount	0	0 – 1	Strength of a second colour band laid across the ramp; 0 removes it.
bg_band_angle	0	0 – 1	Direction the band runs in, independently of the ramp, as a fraction of a turn.
bg_band_pos	0.5	0 – 1	Where across the frame the band sits.
bg_band_width	0.15	0.02 – 1	How wide the band is; narrow reads as a horizon, wide as a wash.
bg_band_curve	0	-1 – 1	Bows the band into an arc instead of a straight line.
bg_band_hue	0	0 – 1	Where the band’s own colour is picked from the palette.
bg_band_hue_span	0	-0.5 – 0.5	How far the band’s colour travels along the palette across its width.